Punjab Mdcat Mock Paper 3 — Solved Past Paper with Answers

Q1. The culpable child _ some words to her mother for pardoning his delinquency.

• A. Mumbled✓
• B. Showy
• C. Rude
• D. Crazy

Explanation: 'Mumbled' is to say something indistinctly and quietly, making it difficult for others to hear. So, the correct sentence is, "The culpable child mumbled some words to her mother for pardoning his delinquency."

Q2. I _ caution in interpreting these results.

• A. Urge✓
• B. Usher
• C. Usurp
• D. Uproot

Explanation: As a noun, 'urge' means a desire. As a verb, it means to strongly encourage. 'Urge' is related to the word, 'urgent' or 'pressing'. An 'urge' is a pressing want, one that is almost a compulsion, like when you're so frustrated, you have the urge to scream. If you urge someone to do something, you feel strongly about it.

Q3. Choose the BEST Option.The region _ which they were passing was known as the Land of Thirst and Death.

• A. Through✓
• B. By
• C. In
• D. From

Explanation: Through can be used as a preposition, an adverb, and an adjective. It has several meanings, including “from one side to the other,” “from beginning to end,” and “during an entire period”: He rode his bicycle through the door and onto the street. You have to read the book through if you want to be prepared for class.

Q4. Choose the BEST Option.It is better for me to _ than to shed the blood of an innocent boy.

• A. Died
• B. Die✓
• C. Had died
• D. Have died

Explanation: Text From ( The Gulistan of Sadi, tale III). The sentence here is in present tense so the verb 'die' will be the best option to use here.

Q5. Select the incorrect segment:The patient’s blood analysis shows that there is a big number of amorphous cells which are quiet unidentifiable.

• A. Patient’s
• B. Of
• C. Which
• D. Quiet✓

Explanation: The right word that should be used at this place is QUITE which means absolutely. QUEIT refers to not saying anything which is not the word required here .

Q6. Select the incorrect segment:Your argument is simply abstruse as there is no clarity of thought and coherence in ideas and it also lack vision.

• A. Is
• B. Of
• C. In
• D. Lack✓

Explanation: As the object described is singular i.e Vision ,the verb used should also be singular. Thus the correct form will be ….it also lacks vision.

Q7. The disease is uncurable without the judicious use of antibiotics.

• A. Uncurable✓
• B. Without
• C. Judicious
• D. Use

Explanation: "Uncurable" is not a word. The correct word is "Incurable".

Q8. Select the incorrect segment:

• A. Discarded
• B. As
• C. There
• D. For✓

Explanation: Error: Use of "for".The preposition "for" must be replaced by "in".

Q9. Choose the CORRECT option:

• A. Are you noticed the peach blossoms?
• B. Have you noticed the peach blossoms?✓
• C. Will you noticed the peach blossoms?
• D. Were you noticed the peach blossoms?

Explanation: Have is used with the pronouns I, you, we, and they, while has is used with he, she, and it.

Q10. She might be forgiven for _ beneath the pressure.

• A. Undertaking
• B. Extricating
• C. Buckling✓
• D. Resounding

Explanation: Buckle means to collapse under weight or pressure hence C is the correct answer.

Q11. Identify the MISTAKE in the following question:When he was a child, every time he were naughty, his foster-mother used to threaten to send him to Timbuktu.

• A. He was
• B. He were✓
• C. Used to
• D. To send him

Explanation: In a past continuous tense, we use was with He, She, and It hence B is the correct answer.

Q12. Choose the correct sentence from the following options:

• A. The government should accrue taxes for strengthen the economy of the country.
• B. The government should accrue taxes in strengthen the economy of the country
• C. The government should accrue taxes to strengthen the economy of the country.✓
• D. The government should accrue taxes by strengthen the economy of the country.

Explanation: By comparing all four sentences ,you notice there is only one difference i.e. PREPOSITION and for fact the best suited is 'to strengthen'.

Q13. She _ about the excitement of hearing the news of her sister’s wedding.

• A. Ran
• B. Jigged✓
• C. Talked
• D. Wept

Explanation: Dance performed out of excitement is called a “jig”, which is the proper context of using this word in this case. Weep means to cry which happens in cases of sadness. Talking and running also does not suit the sense of the sentence.

Q14. The younger sister hopes to emulate her elder sister’s sporting achievement as she is putting up hectic effort.

• A. To
• B. Sister’s
• C. Achievement
• D. Up✓

Explanation: According to rules regarding Phrasal verbs,the correct form is 'putting in' and not 'putting out'.Putting in means make a formal offer.

Q15. Choose the correct sentence from the following options:

• A. Shahid battered Anwar down submission.
• B. Shahid battered Anwar into submission✓
• C. Shahid down battered Anwar into submission.
• D. Shahid was battered Anwar down submission.

Explanation: Option B is correct because it has the most correct sentence structure. It should be into submission not down submission, according to the correct use of grammar. There are only two options having this proper use(B and C). Option C has a major grammatical flaw: “Shahid down battered Anwar” hence it can not be our answer.

Q16. The delegates in Anatolia could transfer their activities to Istanbul, put Mustafa Kamal’s ideas into practice and yet not longer stand in opposition to the Padishah.

• A. In
• B. To
• C. Into
• D. Not longer✓

Explanation: "No longer" would be correct form of expression in this sentence.

Q17. The finger like infoldings, which are formed by inner membrane of mitochondria, are called:

• A. Ribosomes
• B. Matrix
• C. Porin
• D. Cristae✓

Explanation: Factual recall; 'Ribosomes' are organelles, that serve as sites of protein synthesis. 'Matrix' refers to the space confined by the inner mitochondrial membrane within the mitochondria. 'Porin' refers to a transport protein that enables the passive diffusion of certain molecules across a membrane. Cristea are finger-like infoldings, which are formed by the inner membrane of the mitochondria.

Q18. The structure present in a eukaryotic cell but absent in prokaryotic cells is;

• A. DNA
• B. Ribosomes
• C. Cell surface membrane
• D. Nucleus✓

Explanation: The defining difference, between eukaryotic and prokaryotic cells, is membrane-bound organelles including the nucleus. Eukaryotic cells possess membrane-bound organelles but prokaryotes do not.All other three options describe structures common to both, i.e. DNA, ribosomes (which are organelles but not membrane bound), and cell surface membrane.

Q19. Site of mRNA translation

• A. Lysosomes
• B. Ribosomes✓
• C. Cisternae
• D. Golgi body

Explanation: Factual recall;Option A mentions lysosomes, which contain hydrolytic enzymes that digest old organelles or phagocytosed particles.Option B mentions ribosomes; messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain or polypeptide. Option C, cisternae, describes the sac-like tubules that make up the endoplasmic reticulum.Option D, Golgi body, is involved in packaging of already synthesized proteins and their subsequent transport or secretion.

Q20. Among the following, which cellular organelle contains circular DNA, similar to those found in bacteria?

• A. Lysosome
• B. Nucleus
• C. Nucleosome
• D. Mitochondria✓

Explanation: Chloroplasts and mitochondria are the two organelles, that contain circular DNA similar, to those found in prokaryotic cells, along with 70S ribosomes, which are also similar to the ones in prokaryotes, such as in bacteria. This can be traced back to the endosymbiotic theory, where mitochondria and chloroplasts are understood to be ancient prokaryotes.

Q21. A typical neuron at rest:

• A. Is more positive outside than inside✓
• B. Is more negative outside than inside
• C. Has no charge on either side
• D. Has an equal charge on either side

Explanation: Option [A] A typical neuron is more positive outside than inside due to the presence of Na+ K+ pump which countertransports 3Na+ outside and 2K+ inside, removing one extra positive charge outside every time movement occurs.Option[B] At rest neuron is more positive outsideOption [c] Counter-transports of ions occurs in an unequal amount resulting in chargesOption[D] 3 Na+ move outside and 2K+ inside via sodium-potassium pump therefore unequal charge on either side

Q22. Which of the following sequence is correct?

• A. LH → FSH → Estrogen → Progesterone
• B. FSH → LH → Progesterone → Estrogen
• C. FSH → Estrogen → Progesterone → LH
• D. FSH → Estrogen → LH → Progesterone✓

Explanation: [A] FSH is produced in the start in menstrual cycle not LH[B] FSH stimulates the production of Estrogen[C] LH is produced first before progesterone[D] In the start of the menstrual cycle FSH (Follicle Stimulating Hormone)is released during the beginning stimulating the production of Oestrogen from ovaries that vascularise the endometrium and then decrease in FSH and increase in Estrogen Produces LH and after Ovulation corpus Luteum secretes Progesterone.

Q23. Sickle cell Anaemia is an example of which type of chromosomal defect?

• A. Chromosomal rearrangement
• B. Transposition of gene
• C. Chromosomal aberration
• D. Point mutation✓

Explanation: Option [A] chromosomal rearrangement includes inversions,reciprocal translocations that can have effect on gene expression through positive effects Option [B] Transposition of gene is the change in gene position.Option [C] chromosomal aberrations are the mega changes which involve presence of an extra chromosome or loss of chromosome from diploid number of chromosomes.Option [D] In Sickle cell anaemia,the 6th amino acid[ glutamic acid] is replaced by another amino acid [valine] in each haemoglobin BETA chain so haemoglobin is unable to carry out its normal function of carrying oxygen [haemoglobin becomes abnormal].In the nucleotide order,the nitrogenous base thymine is replaced by adenine.Since there is alterations in the sequence of DNA nucleotide so it is an example of POINT MUTATION [If alterations involve one or a few base pairs in the coding sequence they are called point mutation]. Hence option D is right.

Q24. The karyotype of an individual is _ of chromosomes.

• A. Number
• B. Types
• C. Number, types and chemical composition
• D. Number and types✓

Explanation: [A] Does not refer only on number of chromosome[B] does not refer to the type of chromosomes only[C] does not refer to chemical composition of chromosomes[D] Karyotype of an individual refers to complete set of chromosomes that includes the number and set of chromosomes in that set

Q25. Microtubules of spindle fibres are composed of a protein called

• A. Tubulin✓
• B. Actin
• C. Myosin
• D. Troponin

Explanation: [A] The tubulin proteins α- and β polymerize into long chains or filaments that form microtubules.[B] Actin forms microfilaments in the cytoskeleton[C] Myosin protein is found in muscle cells, converts chemical energy in the form of ATP to mechanical energy,generating force and movement[D] Troponin,protein found in the muscles of heart

Q26. Cell death due to tissue damage is called:

• A. Necrosis✓
• B. Metastasis
• C. Apoptosis
• D. Epistasis

Explanation: [A] Necrosis is the death of a body tissue,occurring when too little blood flows to the tissue.[B]Metastasis means that cancer has spread to different parts of body[C] Apoptosis the process of programmed cell death[D] Epistasis is a circumstance where the expression of one gene is modified by expression of one or more gene

Q27. When a disease is transmitted directly from an affected father to his son, it is called:

• A. X-linked
• B. Autosomal
• C. Y-linked✓
• D. X and Y-linked

Explanation: [A] X-linked traits are not only transmitted from father to son but can be also transmitted to her daughter[B] Autosomal disease can be transferred from one parent to a child no specific pattern[C] Y-linked traits transmission occurs only in males so if a mail has a trait so should his father and paternal grandfather as well as his sons and their sons[D] Y-linked is transferred from males to males only but not X-linked

Q28. Which of the following proteins is common in man and aerobic bacteria?

• A. Haemoglobin
• B. Myoglobin
• C. Cytochrome c✓
• D. Pilin

Explanation: [A] Haemoglobin is not found in aerobic bacteria only in man[B] Myoglobin is found in man only[C] found in both man and aerobic bacteria s it plays a key role in ATP synthesis in Mitochondrion[D] pillin found in pious structure of aerobic bacteria only not in man

Q29. The non-protein part of enzyme which is covalently and permanently bonded is called

• A. Prosthetic Group✓
• B. Co-Factor
• C. Coenzyme
• D. Activator

Explanation: Option A: If the non protein part is covalently[permanently] bonded with the protein part of enzyme ,it is known as prosthetic group.[e.g an iron containing porphyrin ring attached to some enzymes like cytochrome.]. So the right option is AThe other options are eliminated as follows:Option B: cofactor is the nonprotein part of enzyme which is required for proper functioning of enzyme. It has 3 types:ActivatorProsthetic groupcoenzymeOption C: coenzyme is the nonprotein part which is organic and loosely attached to the protein part. E.g NADP+/ATPOption D: activator The detachable [means it is loosely attached] co factor is known as an activator if it is an inorganic ion[e.g Mg+,Fe+,Zn+2 etc]

Q30. Acetylcholine and Noradrenaline are two types of _ used in our nervous system:

• A. Enzymes
• B. Channel and carrier proteins in the cell membrane of a neuron.
• C. Neurotransmitters✓
• D. Hormones

Explanation: Factual recall:Both of these substances are neurotransmitters and not any of the things, mentioned in the other options.

Q31. The prokaryotes possess ribosome with larger subunit of:

• A. 70S
• B. 50S✓
• C. 60S
• D. 40S

Explanation: Prokaryotes contain 70S ribosomes, which themselves comprise of two further subunits; a larger 50S subunit and a smaller 30S subunit. 80S ribosomes are present in eukaryotes.

Q32. The route of urine excretion from kidney to outside of body is:

• A. Kidney -> ureter -> urinary bladder -> urethra✓
• B. Urinary bladder -> kidney -> ureter -> urethra
• C. Kidney -> urethra -> urinary bladder -> ureter
• D. Kidney -> ureter -> urethra -> urinary bladder

Explanation: Option A describes the correct route of urine excretion. The kidney filters blood and forms urine. This urine is to be excreted out of the body, and from the kidney, it drains into the ureter. Each kidney drains into one ureter, which is a long muscular tube, that leads into the urinary bladder, which is a sac-like organ that collects urine from the kidney. When a certain amount of urine has been collected, it is urinated out by a thin tube known as the urethra.All of the remaining options describe jumbled up/incorrect routes of urine excretion.

Q33. Which of the following hormone stimulates the ovulation from the follicle into oviduct?

• A. Estrogen
• B. Progesterone
• C. Luteinizing hormone✓
• D. Follicle stimulating hormone

Explanation: Option A, estrogen, is the hormone that causes the development and thickening of the endometrial lining.Option B, progesterone, is the hormone, secreted by the corpus luteum, to maintain and thicken the endometrial lining, making it ready for implantation.Option C, LH, is the main trigger of ovulation, as a surge in LH causes the release of the secondary oocyte from the Graafian follicle into the oviduct. Hence, it is the correct option. Option D, FSH, is responsible for the development of follicles in the ovary.

Q34. Four plants are present in different environmental conditions. Plant A is present in a warm climate with continuous rainfall, plant B is present in a cool forest, plant C is present in a warm climate with little breeze, while plant D is present in a warm climate with high wind speed. Which one of the above plants will have the highest rate of transpiration?

• A. Plant B
• B. Plant D✓
• C. Plant A
• D. Plant C

Explanation: When it comes to questions like these, do not confuse the option letter with the letter of the plant itself. The factors which affect the rate of transpiration are: temperature, as at a higher temperature, more water vapour is given up by the leaves of the plant; humidity, as more humid conditions decrease the concentration gradient of water vapour between the air spaces of the leaves and the atmosphere so, the rate of transpiration decreases; wind speed, as a greater wind speed moves away more of the water vapour collected around the leaves and stomata, thereby increasing the concentration gradient between the air spaces of the leaves and the atmosphere. Plant A has a warm atmosphere but has continuous rainfall. Rainfall would imply a humid atmosphere so, the rate of transpiration is not very high. Plant B has a cool atmosphere so, the rate is low. Plant C is present in a warm climate but the breeze is slow so, when wind speed is low, more water vapour accumulates around the leaves of the plant thereby reducing the concentration gradient between the air spaces and the atmosphere. Hence, the rate of transpiration is not very high. Plant D is present in a warm climate in addition to having a high wind speed so, both factors contribute to a high rate of transpiration. Hence, the option which mentions plant D is the correct answer, which is option B.

Q35. If a heterozygous individual shows the complete effect of both alleles, the type of inheritance would be?

• A. Complete dominance
• B. Codominance✓
• C. Nondominance
• D. Incomplete dominance

Explanation: Codominance is a genetic phenomenon in which both alleles of a gene are expressed equally in the phenotype of a heterozygous individual.

Q36. Following group is the example of acoelomates:

• A. Annelids
• B. Aschelminthes
• C. Molluscs
• D. Platyhelminthes✓

Explanation: The Platyhelminthes are acoelomate flatworms: their bodies are solid between the outer surface and the cavity of the digestive system

Q37. Which one of the following is the main cause of cancer?

• A. Mutation✓
• B. Controlled cell division
• C. Regulated mitosis
• D. Haploid division

Explanation: Cancer is caused by changes (mutations) to the DNA within cells. The DNA inside a cell is packaged into a large number of individual genes, each of which contains a set of instructions telling the cell what functions to perform, as well as how to grow and divide.

Q38. Crossing over takes place during _ of meiosis.

• A. Prophase I✓
• B. Telophase I
• C. Metaphase I
• D. Anaphase I

Explanation: Meiosis consists of two divisions, both of which follow the same stages as mitosis (prophase, metaphase, anaphase, telophase). Meiosis is preceded by interphase, in which DNA is replicated to produce chromosomes consisting of two sister chromatids. A second growth phase called interkinesis may occur between meiosis I and II, however no DNA replication occurs in this stage Meiosis I The first meiotic division is a reduction division (diploid → haploid) in which homologous chromosomes are separated P-I: Chromosomes condense, nuclear membrane dissolves, homologous chromosomes form bivalents, crossing over occurs M-I: Spindle fibres from opposing centrosomes connect to bivalents (at centromeres) and align them along the middle of the cell A-I: Spindle fibres contract and split the bivalent, homologous chromosomes move to opposite poles of the cell T-I: Chromosomes decondense, nuclear membrane may reform, cell divides (cytokinesis) to form two haploid daughter cells.

Q39. _ is the site of light-independent reaction.

• A. Thylakoid membrane
• B. Thylakoid space
• C. Stroma✓
• D. Grana

Explanation: The light-dependent reactions take place on the thylakoid membranes. The inside of the thylakoid membrane is called the lumen, and outside the thylakoid membrane is the stroma, where the light-independent reactions take place. Thylakoids are arranged in stacks called grana. The chloroplast matrix is called the stroma and contains enzymes that catalyse the light-independent reactions of photosynthesis. But stroma is not the site for light reactions. Stromal lamellae connect two or more grana to each other. In this way, the lamellae act as a skeleton of the chloroplast, maintaining efficient distances between the grana, thereby maximising the overall efficiency of the chloroplast. Dark reaction does not depend directly on the presence of light but is dependent on the products of light reaction i.e., ATP and NADPH. The dark reaction occurs through the Calvin cycle.

Q40. In which phase of the cell division is the metabolic activity of the nucleus high?

• A. Mitosis
• B. Interphase✓
• C. Meiosis
• D. Cell Cycle

Explanation: The period of life cycle of cell (cell cycle) between two consecutive divisions is termed as the interphase or misleadingly called resting phase. It is the period of great biochemical activity and can further be divided into G1-phase, S-phase and G2-phase. G1 (Gap 1) is the period of extensive metabolic activity, in which cell normally grows in size, specific enzymes, are synthesized and DNA base units are accumulated for the DNA synthesis.

Q41. Photosystem I has chlorophyll a molecules which absorb maximum light of:

• A. 680 nm
• B. 780 nm
• C. 700 nm✓
• D. 580 nm

Explanation: There are two photosystems, PSI and PSII. these are named so in order of their discovery. Photosystem I has chlorophyll a molecule that absorbs the maximum light of 700nm. Whereas PSII absorbs the maximum light of 680nm.

Q42. The inner membrane of mitochondria form extensive infoldings called:

• A. Cristae✓
• B. Cisternae
• C. Lamella
• D. Bifidae

Explanation: Mitochondria are a double-membranous structure with an outer membrane and an inner membrane.

Q43. Which one of the following organelle is found in both prokaryotic and eukaryotic cells?

• A. Centriole
• B. Endoplasmic Reticulum
• C. Nucleus
• D. Ribosome✓

Explanation: Membrane bounded organelles are absent in prokaryotic cells but present in eukaryotic cells. Ribosomes are non-membranous and are present in both prokaryotic and eukaryotic cells

Q44. Bicuspid valve controls the flow of blood from:

• A. Right atrium to right ventricle
• B. Right ventricle to pulmonary artery
• C. Left ventricle to aorta
• D. Left atrium to left ventricle✓

Explanation: The bicuspid valve, also known as the mitral valve, is located between the left atrium and the left ventricle of the heart. It controls the flow of blood from the left atrium, where oxygenated blood returns from the lungs, to the left ventricle, which pumps the oxygenated blood into the aorta for distribution to the rest of the body.When the left atrium contracts during the cardiac cycle, the bicuspid valve opens, allowing blood to flow from the left atrium into the left ventricle. After the left ventricle contracts, the bicuspid valve closes to prevent the backflow of blood into the left atrium. This valve plays a crucial role in maintaining the one-way flow of blood through the heart.

Q45. The concentration of sodium ions in body fluids is controlled by the hormone:

• A. Renin
• B. Aldosterone✓
• C. Angiotensin
• D. CPK

Explanation: Aldosterone (ALD) is a hormone that helps regulate your blood pressure by managing the levels of sodium (salt) and potassium in your blood and impacting blood volume. Released by adrenal glands.

Q46. The disease in which death of small number of cells in the basal ganglia leads to inability to select and initiate patterns of movement is known as:

• A. Fever
• B. Alzheimer’s Disease
• C. Epilepsy
• D. Parkinson’s Disease✓

Explanation: parkinsson disease is caused by loss of brain cells this cells are associated with release of dopamine .it causes shaking, stiffnessand difficulty balance .parkinson disease is known as the most nostorious disease of of basal ganglia(group of structures linked thalamas to the base of brain)..parkinsson ise a degenerative disease.

Q47. Identify the word or phrase that needs to be changed for the sentence to be correct:We are expecting to go abroad this summer.

• A. Are
• B. Expecting
• C. To go
• D. This
• E. No error✓

Explanation: The above sentence has no error.

Q48. Syphilis is a sexually transmitted disease and can also damage:

• A. Hair
• B. Heart✓
• C. Peripheral Nervous System
• D. Birth canal

Explanation: Syphilis, at its late stages, is known to cause cardiovascular diseases which involve the enlargement of the heart such that the aorta can not keep up with excess blood pressure through dilation and recoilation. It is caused by a spirochaete, Treponema pallidum. It damages the reproductive organs, eyes bones joints, central nervous system, heart, and skin. Sexual contact is the major source of its dissemination.

Q49. The term “Loss of appetite” refers to disease:

• A. Botulism
• B. Anorexia nervosa✓
• C. Obesity
• D. Bulemia nervosa

Explanation: Anorexia nervosa is an eating disorder characterized by an abnormally low body weight, an intense fear of gaining weight and a distorted perception of weight. Botulism is a rare and potentially fatal illness caused by a toxin produced by the bacterium Clostridium botulinum Obesity is a complex disease involving an excessive amount of body fat. Bulimia nervosa, commonly called bulimia, is an eating disorder characterized by an obsession for binge eating.

Q50. Which hormone is released in females in response to FSH from the pituitary gland?

• A. Estrogen✓
• B. ADH
• C. Oxytocin
• D. Progesterone

Explanation: Follicle-stimulating hormone (FSH) from the pituitary gland stimulates the ovaries in females. In response to FSH, the ovaries produce estrogen. Estrogen is a group of hormones that includes estradiol, estrone, and estriol. These hormones play crucial roles in the development and maturation of the ovarian follicles (structures that contain the developing eggs) and in regulating the menstrual cycle.

Q51. DNA made by joining pieces from two or more different sources:

• A. Probes
• B. Restriction endonuclease
• C. Mutated DNA
• D. Recombinant DNA✓

Explanation: Recombinant DNA (or rDNA) is made by combining DNA from two or more sources. DNA probes are stretches of single-stranded DNA used to detect the presence of complementary nucleic acid sequences (target sequences) by hybridization. A restriction enzyme, restriction endonuclease, or restrictase is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.

Q52. Discharge of ovum or secondary oocyte from ovary or from Graffian follicle is called

• A. Fertilization
• B. Pollination
• C. Follicle formation
• D. Ovulation✓

Explanation: Once the Graffian follicle matures, it bursts apart and releases the secondary oocyte, which is known as ovulation.

Q53. The compounds which on hydrolysis yield polyhydroxy aldehyde or ketone subunits are:

• A. Lipids
• B. Prote
• C. Polynucleotides
• D. Carbohydrates✓

Explanation: Final product of the hydrolysis of carbohydrates are monosaccharides such as glucose and fructose. Glucose and fructose are monosaccharides. Polyhydroxy aldehydes and ketones are also called saccharides.

Q54. Which one of the following is the formula structure of D (α) glucose?

• A. Option A✓
• B. Option B
• C. Option C
• D. Option D

Explanation: The structure of D (α) glucose is option A.

Q55. Food enters from stomach into small intestine through:

• A. Pyloric sphincter✓
• B. Semilunar valve
• C. Cardiac sphincter
• D. Diaphragm

Explanation: The pyloric sphineter is a small piece of smooth visceral muscle the acts as a valve and regulates the flow of partially digested food from the stomach to the duodenum.

Q56. There are evidences that high levels of aluminum can lead to the onset of:

• A. Parkinson's disease
• B. Alzheimer's disease✓
• C. Lesch-Nyhan syndrome
• D. Fragile X-syndrome

Explanation: There is evidence that high levels of aluminium may contribute to the onset of Alzheimer's disease.

Q57. Salivary Amylase begins to digest Starch to shorter polysaccharides and then to:

• A. Glucose
• B. Maltose✓
• C. Sucrose
• D. Lactose

Explanation: The enzyme salivary amylase breaks starch into smaller polysaccharides and the then maltose.Maltose is converted to two molecules of glucose by the enzyme maltase.Sucrase breaks down sucrose into glucose and fructose.lactase breaks down lactose (or “milk sugar”) into glucose and galactose.

Q58. The region of the chromosome or, more specifically, the length of the DNA molecule, which has a particular function is called _.

• A. Kinetochore
• B. Locus
• C. Allele
• D. Gene✓

Explanation: The gene is the basic physical and functional unit of heredity. It consists of a specific sequence of nucleotides at a given position on a given chromosome that codes for a specific protein. A kinetochore is a disc-shaped protein structure associated with duplicated chromatids in eukaryotic cells where the spindle fibers attach during cell division to pull sister chromatids apart. In genetics, a locus is a specific, fixed position on a chromosome where a particular gene or genetic marker is located. An allele is one of two, or more, forms of a given gene variant.

Q59. Muscle is made up of many cells which are referred to as

• A. Myofilaments
• B. Myofibrils
• C. Sarcolemma
• D. Muscle Fibers✓

Explanation: Muscle fibers are long cells, which combine to coordinate movement of different parts of the body.

Q60. Which one of the following differentiates directly into mature sperm?

• A. Primary spermatocyte
• B. Secondary spermatocyte
• C. Spermatogonia
• D. Spermatid✓

Explanation: Spermatids are haploid cells that result from the second meiotic division of secondary spermatocytes. They undergo a process called spermiogenesis, which involves extensive structural and morphological changes to transform into mature sperm.

Q61. Each muscle fibre is surrounded by membrane which is called

• A. Sarcomere
• B. Sarcolemma✓
• C. Twitch fibre
• D. Capsule

Explanation: Each muscle fiber is surrounded by the sarcolemma, which also contains the cytoplasm of the cell.

Q62. Last four vertebrae in humans are fused to form a structure called:

• A. Sacrum
• B. Cervical vertebrae
• C. Pubis
• D. Coccyx✓

Explanation: The last 4 vertebrae in humans are fused into a triangular structure known as the coccyx.

Q63. β-cells of pancreas (changed from liver) secrete a hormone that is called

• A. Insulin✓
• B. Glucagon
• C. Antidiuretic hormone
• D. Gastrin

Explanation: Insulin is released by B-cells in the islet of Langerhans in the pancreas and helps maintain the blood sugar level in the body.

Q64. The antibody molecule consists of _ polypeptide chains:

• A. Eight
• B. Four✓
• C. Six
• D. Two

Explanation: An Antibody molecule is made up of 4 polypeptide chains i.e. two heavy chains and two light chains. (PTB page:326)

Q65. Chlorophyll 'a' and chlorophyll 'b' differ in one of the functional groups… Chlorophyll 'a' has:

• A. -CHO
• B. -OH
• C. -CH3✓
• D. -NH2

Explanation: The only difference between chlorophyll-a and b is that chlorophyll-a has methyl (CH3) on the 2nd pyrrole ring and whereas chlorophyll-b has an aldehyde (-CHO) at this point.

Q66. Cilia and flagella are absent in:

• A. Viruses
• B. Bacteria
• C. Higher plants✓
• D. Lower animals

Explanation: Both prokaryotic and eukaryotic cells contain structures known as cilia and flagella. They are motile cellular appendages found in most microorganisms and animals, but not in higher plants since they don't need to move. The explanation is given below.

Q67. If in lipids there is a higher proportion of unsaturated fatty acids then it will be:

• A. Oils✓
• B. Waxes
• C. Phenols
• D. Fats

Explanation: Unsaturated fatty acids are mostly found in oils or more specifically plant oils.

Q68. Which one of the following is a precursor of steroid hormones?

• A. Glycerol
• B. Sterol
• C. Amino acids
• D. Cholesterol✓

Explanation: Option[A] Lipids are made from glycerolOption[b] Sterols are sub groups of steroidsOption[c] Amino acid is the basic unit of protein. Twenty different types of amino acid combine in different arrangements to forms various different proteinsOption [D] All steroid hormones are derived from cholesterol molecules.

Q69. The muscles that control urine in bladder are known as:

• A. Striated muscles
• B. Smooth muscles
• C. Sphincter muscles✓
• D. Circular muscles

Explanation: Option[a] Striated muscles are either skeletal muscles or cardiac muscles not in the urinary bladder.Option[b] Smooth muscles are present throughout the body ,also exists throughout urinary system where it functions to help rid of toxins and maintain electrolyte balance but does not control the urine in bladderOption [C] Bladder has sphincter muscles,which is a smooth voluntary muscles and control the flow of urine out.Option[d] Circular muscles have a role in opening and closing of passages in the human body to regulate the flow of substances

Q70. The disease which causes immobility and fusion of vertebral joints is:

• A. Osteomalacia (soft bones)
• B. Disc slip
• C. Arthritis
• D. Spondylosis✓

Explanation: Options [A] osteomalacia is a group of diseases in which bone resorption outpaces bone deposit[ it means there is more bone depletion than bone deposition].It is the softening of bones.Option [B] disc slip or herniated disc involves the rupture of annulus fibrosis followed by protrusion of the spongy nucleus pulposis.Option [C] arthritis is an inflammatory or degenerative disease that damage joints.Option [D] Spondylosis is the disease which causes immobility and fusion of joint. It is an age related condition in which the joint and cartilage lined disc are affected. So option [D] is right.

Q71. Luteinizing hormone triggers

• A. Cessation of Oogenesis
• B. Breakdown of Oocyte
• C. Ovulation✓
• D. Development of Zygote

Explanation: When LH is released, it triggers an egg to be released, which can be fertilized, i.e. ovulation.

Q72. Calcium ions released during a muscle fiber contraction attach with:

• A. Myosin
• B. Actin
• C. Tropomyosin
• D. Troponin✓

Explanation: Calcium ions which are released bond to troponin, which in turn allows the tropomyosin to give way, thus allowing the muscle to stay contracted.

Q73. The pigment which stores oxygen in muscles is

• A. Hemoglobin
• B. Myoglobin✓
• C. Myosin
• D. Actinomyosin

Explanation: Myoglobin is a protein present in muscles, which has one oxygen-binding site, and its function is to supply muscles constantly with oxygen.

Q74. Thymus gland is involved in maturation of:

• A. Platelets
• B. B-Lymphocytes
• C. Eosinophils
• D. T-Lymphocytes✓

Explanation: The thymus gland is involved in the maturation of T cells, a type of white blood cell that plays a vital role in the immune system. T cells are responsible for cell-mediated immunity, which is a type of adaptive immunity that helps the body fight off infection.

Q75. Antibodies are produced by which of the following lymphocytes?

• A. B lymphocytes✓
• B. A lymphocytes
• C. T lymphocytes
• D. B and T lymphocytes

Explanation: B lymphocytes are a type of white blood cells which produce antibodies, which protect the body against antigens.

Q76. Skin and mucous membranes are part of the body defense system and they form the

• A. Physical barrier✓
• B. Mechanical barriers
• C. Chemical barriers
• D. Biological barriers

Explanation: As mucous membranes are not involved in chemical reactions, instead protect the body from large external particles, thus acting as physical barriers aiding the body’s defense system

Q77. The product(s) of cyclic photophosphorylation is / are:

• A. ATP✓
• B. NADP
• C. NADP and ATP
• D. NADP, ATP, and O2

Explanation: Cyclic photophosphorylation is a process of movements of electrons in a cyclic manner to produce ATP only. NADPH is produced in non-cyclic photophosphorylation.

Q78. Bacteria and fungi are examples of

• A. Producers
• B. Decomposers✓
• C. Consumers
• D. Denvers

Explanation: Bacteria and fungi are examples of decomposers, and gain energy from breaking down dead organisms or waste from other organisms.

Q79. The gene for ABO-blood group systems in humans is represented by symbol

• A. X
• B. I✓
• C. Y
• D. O

Explanation: The gene for ABO blood group systems is represented by I, with the three alleles being IA, IB, and i.

Q80. In men, sex-determination depends upon the nature of

• A. Heterogametic male✓
• B. Homogametic female
• C. Heterogametic female
• D. Homogametic male

Explanation: In humans, the sex is determined by the heterogametic male, who have the XY chromosome, while the female have the XX chromosome.

Q81. Metabolic waste from metabolism of nucleic acid is:

• A. Uric acid✓
• B. Creatine
• C. Urea
• D. Creatinine

Explanation: Option [A] Uric acid is the chemical created when the body breaks down substances called purines,nucleic acid contains purines adenine,GuanineOption[b] Creatine is found naturally in muscle cells,it helps muscles produce energy during heavy lifting or high intensity exerciseOption[c] Urea is produced due to oxidation of excess amino acids in liverOption[d] creatinine is the waste product made by muscles from the normal wear and tear on muscles of the body.

Q82. An activated enzyme consisting of polypeptide and a cofactor is known as

• A. Amylase
• B. Apoenzyme
• C. Holoenzyme✓
• D. Coenzyme

Explanation: Option A is incorrect because Amylase is the enzyme that breakdown carbohydratesOption B is incorrect because Apoenzyme is the enzyme with its cofactor removed it is non functionalOption C is correct since Holoenzyme is an activated enzyme consisting of polypeptide and a cofactorOption D is incorrect because Coenzyme is a type of cofactor that loosely attached to the protein part

Q83. Plastids are only found in the:

• A. Animals and Plants
• B. Animals
• C. Plants✓
• D. Viruses

Explanation: Plastids are double membraned organelles, which contain pigments used in photosynthesis, and also manufacture and store compounds in plant cells.

Q84. The average atomic mass of Boron is 10.8. It has two isotopes of masses 10 and 11 respectively. What is the percentage of isotope with the average mass of 10?

• A. 20%✓
• B. 60%
• C. 80%
• D. 50%

Explanation: The formula for calculating the average atomic mass is[ (Mass of one isotope x percentage abundance) + (mass of other isotope x percentage abundance) divided by 100]. In this question, aside from using the formula for each option which would be a bit time consuming, you can take clues from the question itself. The average mass of Boron is 10.8, which is closer to 11 than 10. As such, you can conclude that the abundance of 10 isotope is lesser than the abundance of the 11 isotope, as such, its abundance MUST be less than 50%. The only option with an abundance less than 50 percent is option A, 20 percent. If you check this with the formula, the answer comes out to be correct:[(10 x 20) + (11 x 80) divided by 100] is 10.8.

Q85. Select the reagent X from the following choices for this conversion:

• A. Acidified Potassium hydroxide
• B. Acidified Potassium dichromate (VI)✓
• C. Acidified Phosphoric acid
• D. Acidified Oxalic acid

Explanation: The reaction above is oxidation of a secondary alcohol into a ketone. As such, an oxidizing agent must be chosen for reagent X. Among the options, 'Potassium dichromate (VI)' is an oxidizing agent so, the correct option is B. Another answer could be 'potassium manganate (VII)', but it is not mentioned in any of the options. The other options do not oxidize alcohols.

Q86. Aqueous solutions of Iodine and Sodium hydroxide were mixed in a round bottom flask at 70 C. Following chemical reaction was carried out. 3I2 + 6 NaOH -> NaIO3 + NaI + H2OThis reaction is termed as;

• A. Redox reaction✓
• B. Precipitation reaction
• C. Substitution reaction
• D. Free radical reaction

Explanation: To determine whether such a reaction is a redox reaction, the oxidation states of the reactants and products is compared. The oxidation state of Na remains +1 throughout, as does the oxidation states of Hydrogen (+1) and Oxygen (-2). Iodine undergoes a change in oxidation state. Its oxidation state is 0, in its molecular form, on the reactant side. In NaI, iodine's oxidation state is -1 so, Iodine has undergone reduction. In NaIO3, the oxidation states of Na remain +1 and oxygen's also remains -2 so, we can determine that the oxidation state of iodine is +5 in this reaction. (NOTE: For oxidation numbers, the total oxidation state of a compound is zero so, Iodine's oxidation number must be +5 to ensure NaIO3’s oxidation state is zero).Since Iodine underwent oxidation AND reduction, we can conclude that this is a redox reaction (disproportionation to be precise, as the same species has undergone oxidation and reduction) so, option A is correct.Option B is incorrect, as the two salts produced are soluble in water.Option C does not describe this reaction.Option D is incorrect as no free radicals are produced during this reaction.

Q87. Which of the following compounds is responsible for the depletion of ozone layer?

• A. Chlorofluorocarbons✓
• B. Carbon tetrachlorie
• C. Methane
• D. Hydroflorocarbons

Explanation: Factual recall.

Q88. Which of the following reactions is used for the production of alcohols on industrial scale?

• A. Hydrogenation of alkenes
• B. Hydration of alkenes✓
• C. Hydrohalogenation of alkenes
• D. Hydroxylation of alkenes

Explanation: Option A describes a reaction that produces alkanes from alkenes. Option B describes a reaction that produces alcohol from alkenes so, it is correct. Option C describes a reaction that produces alkyl halides from alkenes. Option D describes a reaction that produces glycol from alkenes, which is a type of alcohol but not the type that is produced on an industrial scale for commercial use.

Q89. The names of functional groups in the following compound X are:

• A. Secondary alcohol, nitrile, and phenol ring
• B. Secondary alcohol, amine, and benzene ring
• C. Secondary alcohol, nitrile, and aryl ring✓
• D. Primary alcohol, nitrile, and benzene ring

Explanation: The functional groups are: secondary alcohol, nitrile, and benzene/aryl ring.Option A incorrectly mentions phenol as there is no hydroxyl group directly bonded to the benzene ring.Option B incorrectly mentions amine, as for an amine, the nitrogen atom must be bonded to at least three other species/atoms, but in this case, nitrogen is directly bonded to one carbon atom, indicating a C-N triple bond which is characteristic of nitriles.Option C correctly lists all three functional groups.Option D incorrectly mentions primary alcohol, as for the alcohol group to be primary it must have been terminal/present at the end of the alkyl group, which is not the case here as -OH group is mentioned in the structural formula as being in the middle of the alkyl group.

Q90. Which of the following catalysts is used in the below reaction?

• A. Conc. H2SO4✓
• B. Purnice stone
• C. Pt
• D. Ni

Explanation: Esterification process is a slow process when it is performed at room temperature also the process does not complete at all in the room temperature. So to complete the process of esterification there should be something to complete the process as well as to speed up the process. Thus concentrated sulphuric acid is added. It is a catalyst which will speed up the process and esterification will proceed speedily and complete on time. Also concentrated sulphuric acid has a property to remove water. Therefore it also acts as a dehydrating agent. After adding this will take reaction in the equilibrium position and will be able to give a greater yield of ester as result.

Q91. In antibody molecule, two heavy and two light chains are bonded by:

• A. Disulphide Bond✓
• B. Monosulphide Bond
• C. Hydrogen Bond
• D. Ionic Bond

Explanation: "The explanation for this question will be added soon!".

Q92. During the SN1 reactions, the fast reaction involves:

• A. Breakage of covalent bond
• B. Formation of carbocation
• C. Transition state
• D. Attack of nucleophile✓

Explanation: The nucleophile has a negative / partially negative charge and it readily attacks the carbocation in SN1 reactions (which has a positive charge) This is the fast step of the reaction.

Q93. Alcohol in which carbon atom bonded to OH group is further attached with three alkyl group is:

• A. Tertiary alcohol✓
• B. Primary alcohol
• C. Aromatic alcohol
• D. Secondary alcohol

Explanation: A tertiary (3°) alcohol is one in which the carbon atom with the OH group is attached to three other carbon atoms. Its general formula is R3COH Primary alcohols are those alcohols where the carbon atom of the hydroxyl group (OH) is attached to only one single alkyl group. The aromatic alcohols or aryl-alcohols are a class of chemical compounds containing a hydroxyl group (—OH) bonded directly to an aromatic hydrocarbon group. A secondary alcohol is a compound in which a hydroxyl group( ‒OH) is attached to a saturated carbon atom which has two other carbon atoms attached to it.

Q94. 3.0 mole of Calcium will contain _ g of Calcium.

• A. 105 g
• B. 120 g✓
• C. 80 g
• D. 100 g

Explanation: Moles of Calcium = 3 Molar mass of Calcium (Ca) = 40 Mass of Calcium in grams = ? Moles = Mass/Molar mass Mass = Moles × Molar mass Mass = 3 x 40 => Mass 120grams

Q95. Which one of the following reagents is used to distinguish between aldehydes and ketones?

• A. Alkaline Iodine
• B. Tollen’s Reagent✓
• C. Bromine
• D. 2, 4 DNPH

Explanation: The Tollens' test is a reaction that is used to distinguish aldehydes from ketones, as aldehydes are able to be oxidized into a carboxylic acid while ketones cannot.Alkaline iodine is used in the iodoform test. When Iodine and sodium hydroxide are added to a compound that contains either a methyl ketone or a secondary alcohol with a methyl group in the alpha position, a pale yellow precipitate of iodoform or triiodomethane is formed. It can be used to identify aldehydes or ketones.A solution of bromine in CH2CL2 is used to either test for unsaturation or to check the ability to be oxidized for example in aldehydes. Bromine solution is naturally orange and when consumed in oxidation, it becomes colourless.2, 4 DNPH is used to detect ketones and aldehydes. A positive test is signalled by the formation of a yellow, orange or red precipitate of the dinitrophenylhydrazone.

Q96. In an aqueous solution, amino acids exist in an ionic form as shown below: This ionic form of amino acid is known as:

• A. Zwitterion✓
• B. Amphoteric ion
• C. Cation
• D. Anion

Explanation: A zwitterion is a compound with no overall electrical charge, but which contains separate parts which are positively and negatively charged. In an aqueous solution, the carboxyl group can lose a proton (becomes a basic group) and the amino group can accept a proton (becomes acidic) giving rise to the dipolar ion known as Zwitterions.An amphoteric compound is a molecule or ion that can react both as an acid and as a base.

Q97. Halogens are being used as fire extinguishers, mild antiseptic CFCs and many other organic chemicals, Which of the following halogen is used to kill the bacteria in drinking water.

• A. Bromine
• B. Fluorine
• C. Chlorine✓
• D. Iodine

Explanation: One of the easiest and cost effective way to clean water is to add some amount of chlorine into it. But if chlorine is added in excess then the water becomes unfit for consumption. So, when chlorinated water from treatment plants is disposed into rivers etc then it becomes harmful for aquatic species as excess of chlorinated water can lead to death of living beings. Hence, chlorine must be removed from water before releasing the water from water treatment plants into rivers, lakes or oceans.

Q98. Dry distillation of a mixture of calcium salts of formic acid and acetic acid results into the formation of

• A. Formaldehyde
• B. Acetaldehyde✓
• C. Calcium acetate
• D. Sodium acetate

Explanation: A is incorrect because formaldehyde is formed by calcium salt of formic acid onlyB is correct since dry distillation of a mixture of calcium salts of formic acid and acetic acid result into the formation of acetaldehyde and CaCO3 as by-productC is incorrect because dry distillation of a mixture of calcium salts of formic acid and acetic acid do not form calcium acetateD is incorrect because dry distillation of a mixture of calcium salt of formic acid and acetic acid do not form sodium acetate

Q99. In the structure of NaCl, each Na+ is surrounded by _ Cl- ions.

• A. Four
• B. Eight
• C. Five
• D. Six✓

Explanation: A is incorrect as 6 electrons are present around each Na+ in a NaCl structure.B is incorrect as 6 electrons are present around each Na+ in a NaCl structureC is incorrect as 6 electrons are present around each Na+ in a NaCl structureD is correct as 6 electrons are present around each Na+ in a NaCl structure.NaCl has a cubic crystal system and a face-centered cubic crystalline structure. NaCl has four cations and four anions in a face-centered cubic unit cell.

Q100. The charge of one gram of electron is:

• A. 1.7588 x 10-11
• B. 1.7588 x 1011
• C. 1.602 x 10-19
• D. 1.7588 x 108✓

Explanation: A is incorrect as given value is not charge of one gram of electrons.B is incorrect as given value is charge of one kilogram of electrons.C is incorrect as given value is not charge of one gram of electrons.D is correct as given value is charge of one gram of electrons.It can be obtained by dividing the charge of one kilogram of electrons by 1000

Q101. The ionization energy of hydrogen atom is :

• A. Zero
• B. 13.13 kJmol-1
• C. 1313.31 kJmol-1✓
• D. 1313.31 k2Jmol

Explanation: A is incorrect since the ionization of energy of hydrogen is not zero.B is incorrect as the given value is not the ionization energy of hydrogen.C is correct as 1313.3 kJ mol-1 is minimum energy required to remove one electron from the outershell of a hydrogen atom.D is incorrect as given value is not ionization energy of hydrogen

Q102. The number of bonds in nitrogen molecule is

• A. One σ and two π✓
• B. One σ and one π
• C. Three σ only
• D. Two σ and one π

Explanation: A is correct since nitrogen molecule has three bonds one σ and two π.B is incorrect because nitrogen molecule has two π bondsC is incorrect because nitrogen molecule also contain π bondsD is incorrect because nitrogen molecule has only one σ bond

Q103. The standard enthalpy of solution of NH4Cl is _ kJmol-1.

• A. +16.2✓
• B. -25.0
• C. +4.98
• D. +26.0

Explanation: A is correct since enthalpy of solution is +16.2kJmol-1B, C and D are incorrect because the given values of enthalpy are not correct.

Q104. Metallic conduction involves the relatively free movement of their _ throughout the metallic lattice.

• A. Atoms
• B. Molecules
• C. Electrons✓
• D. Ions

Explanation: A is incorrect In metals atoms are not in combined form they are in electron pool type arrangementB is incorrect In metals molecules do not existC is correct since In metals electrons are in pool type arrangement and the can move within metal so the play their role in conductionD is incorrect because In metals ions are not present

Q105. Study the following redox reaction and answer the following question: 10Clˉ +16H+ + 2MnO4ˉ → 5Cl2 + 2Mn2+ + 8H2O

• A. Manganese is oxidized from +7 to +2
• B. Chlorine ions are reduced from -1 to zero
• C. Chlorine is reduced from 0 to -1
• D. Manganese is reduced from +7 to +2✓

Explanation: The correct change in oxidation numbers

Q106. Value of Ksp for PbSO4 system at 25 °C is equal to:

• A. 1.6 x 10-5 mol2dm-6
• B. 1.6 x 10-6 mol2dm-6
• C. 1.6 x 10-8mol2dm-6✓
• D. 1.6 x 10-7 mol2dm-6

Explanation: The question is knowledge based and it can be solve that way (from punjab text book page no243) The solubility of PbSO4 at 25 degrees is 0.038 ​PbSO^-4 ⇌Pb^+2+SO4^2− ​s=mass/molar mass So S =1.254×10^−4 Here we need s^2 So S^2 =1.573×10^-8

Q107. R1R2C=N−NH2 It is the general formula of:

• A. 2,4-Dinitrophenyl hydrazine
• B. 1, 3-Dinitrophenyl hydrazone
• C. Phenyl hydrazone
• D. 2,4-Dinitrophenyl hydrazone✓

Explanation: One important thing which confuses student is that they intermix Phenyl Hydrazine and Phenyl Hydrazone. Hydrazone consists of carbon–nitrogen double bond i.e R1R2C=N−NH2. In Phenyl hydrazone, one H atom of hydrazone is replaced by phenyl ring. Now if we attach two nitro groups at position 2 and 4, as given in the question, the product we have is 2,4-Dinitrophenylhydrazone.

Q108. The type of structural isomerism which arises due to the differences in nature of carbon chains or carbon skeletons is:

• A. Chain isomerism✓
• B. Position isomerism
• C. Cis-Trans isomerism
• D. Optical isomerism

Explanation: In chain isomerism, the molecular formula of the isomers is same but they differ in the carbon chain or carbon skeleton.

Q109. What will be the exact product?

• A. Diethyl ether
• B. Methyl propyl ether
• C. Ethyl acetate✓
• D. Butyl alcohol

Explanation: Ethyl Acetate is an ester that is made when Ethanoic acid reacts with Ethanol.

Q110. Which option shows all the molecules with bond angle 109.5 degrees.

• A. CH4 , NH4+ , PH3
• B. SiCl4 , H2O , BeCl2
• C. SiCl4 , NH4+ , CH4✓
• D. CH4 , CCl4 , NH3

Explanation: Since all molecules stated in option C are tetrahedral in shape, where a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. Hence they all have bond angles that are 109.5 degrees.

Q111. In the formation of Zwitter ion which one of the following donates the proton?

• A. COOH✓
• B. NH2
• C. CH2COO-
• D. OH-

Explanation: Zwitter ions are the ions having two functional groups they contain both positive and negative charge and are considered neutral they are also called inner salts,one of the common example of zwitter ion is protein where a proton is transferred from COOH tO NH2 but the charge of COO- and NH3+ will be balanced internally.

Q112. Mg + 1/2 O2(g) → MgO(g) H=-692 kJmol-1 at STP. Enthalpy of the above reaction will be called:

• A. ΔH°at
• B. ΔH°s
• C. ΔH°sol
• D. ΔH°f✓

Explanation: Here 1 mole of MgO is forming from its constituent elements(Mg and O) so enthalpy here is enthalpy of formation which is defined as the change in enthalpy when one mole of compound is formed from its respective elements in standard state

Q113. 2A + B → Product If the reactant ‘B’ is in excess, the order of reaction with respect to ‘A’ in given rate law, Rate = k[A]2[B] is

• A. 2nd order reaction✓
• B. 1st order reaction
• C. Pseudo 1st order reaction
• D. 3rd order reaction

Explanation: Rate equation is mentioned and in case rate equation specially order of reaction is mentined then they are the only things to be considered In THIS CASE ORDER OF REACTION IS=2+0=2 (SECOND ORDER)

Q114. Nitrogen gas reacts under _ conditions:

• A. Standard
• B. Normal
• C. Cool
• D. Harsh✓

Explanation: Nitrogen gas is a molecule with triple bond between the atoms, which makes Nitrogen unreactive under normal conditions as it takes a lot of energy to break the N-N bond

Q115. Ethanol reacts with HCN to form cyanohydrin. This is an example of:

• A. Nucleophilic addition✓
• B. Electrophilic addition
• C. Electrophilic substitution
• D. Nucleophilic substitution

Explanation: It is an example of nucleophilic addition. The CN- ion has a negative charge and it is attracted to a positive charge so CN- is a nucleophile. CN- forms a sigma bond with the electron-deficient species i.e. C of ethanol.

Q116. A sample of an organic compound consisting of carbon, hydrogen and oxygen was subjected to combustion analysis. 0.5439g of this compound gave 1.039g of carbon dioxide and 0.63469g of water vapours. The empirical formula of this compound is:

• A. CH2O
• B. C4H12O2
• C. C2H6O✓
• D. CH4O

Explanation: Convert g CO2 to g C. Convert g H2O to g H. g O = total g - g C - g H g C = g CO2 x (C/CO2) = 1.039 x 12.01/44.01 = approx 0.2833g g H = g H2O x (2H/H2O) = 0.63469 x (2/18) = 0.07052g g O = .5439-0.07052-0.2833 = about 0.1900 Now covert g C, g O, g H to mols. mols C = 0.2833/12 = about 0.0237mol mols H = 0.0705/1 = about 0.0705mol mols H = 0.0705/1 = about 0.0705mol Now find the ratio of these elements to each other with the lowest number no less than 1.00 and round to whole numbers. The easy way to do that is to divide the smallest number by itself (making sure that is 1.00), then divide the other two numbers by the same small number. Here is what you have: C = 0.0237 H = 0.0705 O = 0.0119. Divide each by 0.0119. C = 0.0237/0.0119 = 1.99 = 2.0 H = 0.0705/0.0119 = 5.92 = 6.0 O = 0.0119/0.0119 = 1.0 So the empirical formula is C2H6O.

Q117. Butane molecules can have a maximum number of isomers.

• A. 5
• B. 3
• C. 4
• D. 2✓

Explanation: Butane is an alkane with four carbon atoms so the molecular formula is C4H10. It has two isomers; n-butane and isobutane.

Q118. The ionic radius of fluoride ion is:

• A. 72 pm
• B. 95 pm
• C. 136 pm✓
• D. 157 pm

Explanation: Atomic radius of fluorine is 62pm but when an electron is added then affective nuclear charge decreases so ionic radius of anion is always grater than atomic radius so for fluoride it is 136pm Key point..flouride is anion of fluorine

Q119. Which one of the following is anhydride of sulphuric acid?

• A. Sulphur (III) oxide✓
• B. Sulphur (VI) oxide
• C. Iron pyrite
• D. Sulphur (VI) oxide

Explanation: Anhydires are formed from elimination of water from a compound in case of H2SO4 after elimination of H2O ANhdride wil be SO3 So anhydride of sulphuric acid is sulphur trioxide SO3+H20—---->H2SO4

Q120. Which one of the following reactions shows combustion of a saturated hydrocarbon?

• A. C2H4 + 3O2 → 2CO2 + 2H2O
• B. CH4 + 2O2 → CO2 + 2H2O✓
• C. CH4 + ½ O2 → CH3OH (Conditions:Cu, 400°C, 200 atm)
• D. C2H2 + 5/2 O2 → 2CO2 + H2O

Explanation: Key points here 1-product of combustion are always H2O and C02 2-saturated mean those having in which carbon form only single bonds

Q121. Which one of the following is an appropriate structure of product of bromination?

• A. Option A
• B. Option B
• C. Option C✓
• D. Option D

Explanation: We are asked to tell the possible product of bromination. From the question we can possibly conclude that OH group is already present on the benzene ring or in other words we are considering phenol. So we have to tell the possible product of the bromination of “phenol”. As OH is ortho para directing group. So the option having product that has Br on Ortho and Para positions is the right one which in this case is the option C

Q122. A researcher has prepared a sample of 1-bromopropane from 10g of 1-propanol. After purification he had made 12g of product. Which of the following is percentage yield?

• A. 60%
• B. 58%✓
• C. 90%
• D. 50%

Explanation: The above question states that 1-bromopropane i.e CH3-CH2-CH2-Br has a molar mass of 123g is being prepared from 10g of 1-propanol i.e CH3-CH2-CH2-OH whose molar mass is 60g, we need to figure out the percentage yield as the given mass of product formed after purification is 12g, the ACTUAL YIELD. Our first step is to find out the theoretical yield which is the quantity of product calculated from a balanced chemical equation The balanced chemical equation is given below, the following reaction is an example of SN2 reaction CH3CH2CH2OH + HBr ============> CH3CH2CH2Br Since we know, 60g of propanol reacts to form 123g of bromopropane, then how many grams of bromopropane will be formed if 10g of propanol reacts? Using conversion factor: 20.5g is the THEORETICAL YIELD. The next step is to find the percentage yield The formula for percentage yield is given as under %yield= actual yield/ theoretical yield x 100 Plugging in the values, we get = 12g/ 20.5 x 100 = 58.5% Hence the correct answer is B, as the value 58.5 is closest to option B.

Q123. Study the following graphs for the boiling points of some substances Which of the above graph shows that some members of the graph have hydrogen bonding:

• A. I + IV
• B. II + IV
• C. III + IV + V✓
• D. I + II + III

Explanation: Hydrogen bonding is found between hydrogen atom of one molecule (which is covalently bonded to an electronegative atom) and flourine, oxygen and nitrogen of other molecule. It is represented with dotted lines.

Q124. In the below reaction the nucleophile which attacks the carbon atom of acid is:

• A. OH-
• B. P
• C. Cl-✓
• D. H-

Explanation: A negatively charged nucleophile attacks through the electrophilic carbon of a haloalkane. Upon attack, the leaving group, which is the halogen of the haloalkane, leaves.

Q125. The skeletal formula of dipeptide formed between aspartic acid and phenylalanine is given below: How many functional groups are present in its formula?

• A. 5✓
• B. 2
• C. 4
• D. 3

Explanation: Carboxylic acid (COOH), Amine (NH2), Amide (O=C-NH), ester (O=C-O-), phenyl (benzene ring).

Q126. The following dipeptide is called:

• A. Glycyl glycine
• B. Glycyl alanine✓
• C. Alaninyl alanine
• D. Alaninyl glycine

Explanation: It is being formed by the removal of a water molecule when glycine is linked to alanine. It is a dipeptide formed from glycine and L-alanine residues.

Q127. The average bond energy of C-Br is

• A. 228 kJmol-1
• B. 200 kJmol-1
• C. 250 kJmol-1
• D. 290 kJmol-1✓

Explanation: Keypoint >Knowledge based question values has to be remember orally >solution: C-C bond energy is 346kcal for each carbon it is 173kj/mol Br-br bong energy it is 194kcal for each carbon it is 96.3kj/mol For C-Br bond energy will 173+96.3 =270kj/mol Nearest value to 270 is 290

Q128. Which one of the following is an appropriate indication of positive iodoform test?

• A. Formation of H2O
• B. Release of H2 gas
• C. Brick red precipitate
• D. Yellow crystal✓

Explanation: If iodoform test is positive than yellow crystals appear Iodoform test is given by following groups 1- Iodoform test is given -CH3C=O groups Functional Groups giving iodoform test are

Q129. Which one of the following reaction of carboxylic acid is reversible?

• A. Esterification✓
• B. Salt formation
• C. Reaction with PCl5
• D. Reaction with SOCl2

Explanation: In esterification, a carboxylic acid reacts with an alcohol, in presence of acid to form ester and water. The reaction is reversible since ester and water can react to form the carboxylic acid and alcohol again.

Q130. .Select the best option indicating the name of the structure given below

• A. Cation
• B. Neutral Amino Acid
• C. Internal Salt✓
• D. Anion

Explanation: There is an internal transfer of a hydrogen ion from the -COOH group to the -NH2 group to leave an ion with both a negative charge and a positive charge. This is called a zwitterion or internal salt.The term internal salt refers to Dipolar character of amino acids.

Q131. The E0 value of the standard copper half cell is 0.34, measured when it is connected withthe SHE i.e. Standard Hydrogen Electrode. In this case the half cell reaction taking place atSHE is:

• A. 2H+(aq) + 2e---------> H2(g)
• B. H2(g) ----------> 2H+ (aq) + 2e-✓
• C. 2H+ (aq) + 2e- --------> 2H(g)
• D. 2H2- ----------> 2H(g) + 2e-

Explanation: Explanation is given below.

Q132. SO3 formed in the contact process is absorbed in _% H2SO2

• A. 90
• B. 80
• C. 98✓
• D. 89

Explanation: In contact process, SO3 is formed in 98% of H2SO2

Q133. Grignard reagents are prepared by the reaction of magnesium metal with alkyl halides in the presence of

• A. Dry Ether✓
• B. Sodium Lead Alloy
• C. Alcohol
• D. Water

Explanation: A is correct since Grignard reagents are prepared by the reaction of magnesium metal with alkyl halides in the presence of dry etherB is incorrect because sodium lead alloy is not use for preparation of Grignard reagentC is incorrect because alcohol is not used because it is reactiveD is incorrect because water is not used because it is reactive

Q134. Methanol is prepared from carbon monoxide and hydrogen. The catalyst used for this reaction is

• A. ZnO + CoO2
• B. ZnO + CuO
• C. ZnO + Ag2O
• D. Cr2O3 + ZnO✓

Explanation: A is incorrect because for preparation of methanol the compound CoO2 is not used as catalystB is incorrect because for preparation of methanol the compound CuO2 is not used as catalystC is incorrect because for preparation of methanol the compound Ag2O is not used as catalystD is correct since the catalyst used for preparation of methanol is Cr2O3 and ZnO is used at temperature of 450 C and 200 atm pressure

Q135. Alanine is an aminoacid which shows neutral effect on litmus paper,the formula of alanine may be

• A. A✓
• B. B
• C. C
• D. D

Explanation: In a neutral amino acid, the number of basic groups (-NH2) is equal to the number of acidic groups (-COOH).

Q136. An organic compound has the empirical formula C3H3O if the molar mass of the compound is 110.15 g.mol-1. The molecular formula of this organic compound is: (A, of C=12, H=1.008and O=16)

• A. C6H6O2✓
• B. C3H3O
• C. C9H9O3
• D. C6H6O3

Explanation: Empirical formula mass= 55 Molecular mass= 110. Therefore, multiply the empirical formula by 2 to get C6H6O2

Q137. The number of molecules in 22.4 dm3 of H2 gas at 0 °C and 1 atm are

• A. 60.2 x 10^23
• B. 6.02 x 1022
• C. 6.02 x 1025
• D. 6.02 x 1023✓

Explanation: This is Avogrado's number of molecules, 6.02×10^23

Q138. Keeping inview the values of standard reduction potential given above, which one of the following would you select as a feasible redox chemical reaction?

• A. Cl- + I2 -> Cl2 + 2I-
• B. Cu + Zn2+ -> Cu2+ + Zn
• C. Mg + 2H + -> Mg2+ + H2✓
• D. 2Au + 6H+ -> 2Au3+ + 3 H2

Explanation: For a redox reaction to be feasible, the emf of it must be positive. (NOTE: When calculating emf, you take the voltage of each half equation according to the scenario, i.e. one will exhibit the same order as those shown above so, the E value is directly taken, but for some, you have to reverse the sign of the E value since the reaction, itself, is reversed). In option A, the emf is = -1.36 + 0.54 = -0.82, so NOT FEASIBLE. In option B, the emf is = -0.34 -0,76 = -1.10, so NOT FEASIBLE. In option C, the emf is = 2.37 + 0.00V = 2.37 so, it IS FEASIBLE; answer is C. In option D, the emf is = -1.50 + 0 = -1.54 (the coefficient of the reaction is not taken into account) so, it is NOT FEASIBLE.

Q139. Kirchhoff's first law/rule corresponds to:

• A. Law of conservation of energy
• B. Law Of conservation Of momentum
• C. Law of conservation of charge✓
• D. Law of conservation of mass

Explanation: Kirchhoff's first law states that the algebraic sum of current flowing into a junction is zero. This rule corresponds to conservation of charge which states that total charge in a closed system remains constant because current is the rate of flow of charge.

Q140. The area under the extension-load graph Of an elastic material whose elastic limit has not been exceeded gives its:

• A. Stress
• B. Strain energy✓
• C. Strain
• D. Young modulus

Explanation: Strain energy is the energy stored by an object undergoing deformation. Area under the extension-load graph represents work done to cause the deformation. An object which has not reached its elastic limit, the work done during stretching is recovered when it is unloaded.

Q141. Heavy nucleus of atoms go through fission so that they can:

• A. absorb low amount of energy
• B. absorb high amount of energy
• C. reduce their binding energy nucleon
• D. increase their binding energy per nucleon✓

Explanation: Maximum binding energy is achieved around Z = 50 (Iron is close to peak at Z = 56). Heavy nuclei undergo fission to decrease nuclear size and increase binding energy per nucleon.

Q142. An object is moving along a circular path of radius 4m. What will be its angular displacement if it moves 14 m on this circular path?

• A. 5.0 radians
• B. 3.5 radians✓
• C. 4.5 radians
• D. 5.5 radians

Explanation: Arc length = Radius x Angular displacementKeeping Arc length as 14m and radius as 4m we get angular displacement

Q143. In relation, which quantity is represented by λ?

• A. Decay constant✓
• B. Half life
• C. Activity
• D. Wavelength

Explanation: Explanation is given below.T1/2 represents the 'half-life' with 'T', implying the quantity has something to do with time, and '1/2' representing 'half'.

Q144. A particle, carrying a charge of 5e, falls through a potential difference of 25 V. What would be energy acquired by the particle in ‘J’.

• A. 1.6 x 10-19 J
• B. 125 J
• C. 125 x 10-19 J
• D. 125 x 1.6 x 10-19 J✓

Explanation: Electric Potential Energy = Electric Potential x Charge Charge = 5 x 1.6 x 10-19 C Electric Potential Energy = 25V x (5 x 1.6 x 10-19) C This could be manipulated to give us (125 x 1.6 x 10-19) J, which is Option D.

Q145. The kinetic energy K.E. with which the electron strikes the target is given by:

• A. K.E. = e2V
• B. K.E. = hc/λ
• C. K.E. = hf2
• D. K.E. = eV✓

Explanation: An electron cannot travel at the speed of light, unless the wave properties are being studied it's wavelength cannot be observed; however eV is a frequent way to describe energy of an electron. Where ‘e’ is the charge of the electron and ‘V’ is the potential difference between the filament and the positive accelerating electrode

Q146. If an electron in the ‘K’ shell is removed and an electron from ‘L’ shell jumps to occupy the hole in the ‘K’ shell, it emits a photon of energy:

• A. hfKα = EL – EK✓
• B. hc = EL – EK
• C. h/λKα = EL – EK
• D. hfKα = EK – EL

Explanation: E=hf. The energy emitted by the electron as it jumps from the higher orbit L to the lower orbit K is thus given by hf=EL - EK

Q147. A radioactive nuclide decays by emitting an alpha particle, a beta particle and a gamma ray photon, the change in the nucleon number will be:

• A. -4✓
• B. -1
• C. -2
• D. -3

Explanation: An alpha particle is a helium nucleus with two protons and two neutrons which means it has a mass number of 4. (42α)A beta particle is a fast-moving electron. An excess neutron transforms into a proton and an electron.The proton stays in the nucleus and the electron is ejected energetically. Therefore in beta emission, the nucleon number remains the same. (01β)In gamma radiation, no particle is emitted instead there is the emission of radiation hence no change in nucleon number occurs during gamma emission(00γ)Therefore, the change in nucleon number will only be caused by the emission of an alpha particle hence the change will be -4.

Q148. A force ‘F’ is acting at point ‘P’ of a uniform rod capable of rotating about ‘O’. What is the torque about ‘O’?

• A. (OP)(F tanϴ)
• B. (OP)(F)
• C. (OP)(F sinϴ)
• D. (OP)(F cosϴ)✓

Explanation: Torque is the cross product between the distance vector (the distance from the pivot point to the point where force is applied) and the force vector,It is important that the force being applied is perpendicular to the rotational axis therefore we will use a component of force F which is perpendicular to the rotational axis. Since the angle θ is between the force F and the perpendicular. The force applied on the rotational axis for torque will be Fcosθ.The distance given here is OP and the force applied is Fcosθ.Torque = d x FTorque = (OP)(Fcosθ)

Q149. Work done, due to centripetal force, for circular motion will be:

• A. Reduced
• B. Zero✓
• C. Maximum
• D. Half

Explanation: The displacement of an object after one complete revolution is 0 as the object returns to its original position. As work done = force x displacement, given the displacement is 0, work done is also 0.

Q150. In a practical transformer mutual induction between primary and secondary coils takes place. In such transformer what can be deduced about the power.

• A. Power output = Power input
• B. Power output > Power input
• C. Power output ≥ Power input
• D. Power output < Power input✓

Explanation: The output power in a transformer is always less than the input power because of the different losses in a transformer. The losses may be Iron loss or core loss, hysteresis loss, eddy current loss, copper loss etc.

Q151. Which of the following compounds, in the form of aqueous solution, on reaction with sodium carbonate will produce carbon dioxide gas?

• A. H3C-COO-C2H5
• B. H3C2-COO-CH3
• C. H3C2-CO-OH✓
• D. H3C2-COO-C2H5

Explanation: A is incorrect as the compound given is an ester which does not produce carbon dioxide upon reaction with sodium carbonate.B is incorrect as it is also an ester,hence it also doesnt produce carbon dioxide upon reaction with sodium carbonate.C is correct as the compound given is a carboxylic acid,it produces carbon dioxide upon reaction with sodium carbonate.D is incorrect as the given compound is unreactive with sodium carbonate.

Q152. The life time of an electron in an excited state is about 10-8 s. What is its uncertainty in energy during this time?

• A. 1.05 x 10-41 J
• B. 1.05 x 10-26 J✓
• C. 1.15 x 1010 J
• D. 2.19 x 10-40 J

Explanation: Excited state time of the electron=10^-8sRequired:Uncertainty in energyDeltaE=h/DeltatBy putting values in formulaAns will be B.

Q153. In the half-life of an element, the equation for the number of decaying atoms is given by:

• A. ΔN ∝ -NΔt✓
• B. ΔN = KNΔt
• C. ΔN ∝ -nΔt
• D. ΔN = -ΔNΔt

Explanation: A)is correct, The number of decaying atoms is directly proportional to the number of radioactive atoms at the time interval deltat.B,C and D are incorrect since the given equations doesnot represent the number of decaying atoms.

Q154. CH3CN + HCl → A + B (in the presence of water)In the reaction given above, A and B are

• A. Acetic acid and acid amide
• B. Acetic acid and ammonia
• C. Acetic acid and methyl chloride
• D. Acetic acid and ammonium chloride✓

Explanation: Chemical reaction: 2CH3CN + 2HCl + 4H2O → 2CH3COOH (acetic acid) +2NH4Cl (ammonium chloride)

Q155. In a radioactive phenomenon observation shown in figure where α deviates lesser than β in some electric or magnetic field (not shown in figure). What is the reason for less deviation of?

• A. α is charged particle
• B. α is neutral particle
• C. α is heavier particle✓
• D. α is lighter particle

Explanation: In a magnetic or electric field, deviation occurs to the charge of a particle and how much a particle deviates depends on the mass of a particle. An alpha particle is identical to the nucleus of the Helium-4 atom. It consists of two protons and two neutrons bound together having a mass of four units and a positive charge of two. A gamma particle has no charge and no mass, hence it is undeflected. A beta particle has a negative charge and lower mass as compared to an alpha particle.Alpha particles deflect the least because it is heavier than beta and gamma.42α ,0-1β ,00γ .

Q156. If ‘m’ is the mass, ‘c’ is the velocity of light and x = mc2, then dimensions of ‘x’ will be:

• A. [LT-1]
• B. [ML2T-2]✓
• C. [MLT-1]
• D. [MLT-2]

Explanation: The equation x = mc² represents the relationship between mass and energy, where x is the energy equivalent of a mass m, and c is the speed of light.To determine the dimensions of x, we need to consider the dimensions of each variable in the equation. The dimensions of mass are [M], the dimensions of the speed of light are [LT-1].Using the rules of dimensional analysis, we can find the dimensions of x by substituting the dimensions of m and c into the equation and simplifying:x = mc²= [M][LT-1]²= [M][L2T-2]Therefore, the dimensions of x are [ML2T-2], which is option B.

Q157. Flow speed of the fluid through a non-uniform pipe increases from 1 m/sec to 3 m/sec. If change in P.E. is zero, then pressure difference between two points will be: (density of the fluid = 1000 kg/m3)

• A. 1000 N/m2
• B. 9000 N/m2
• C. 8000 N/m2
• D. 4000 N/m2✓

Explanation: P1 - P2= 1/2ρ (v12-v22)∆P=½ ρ (v12-v22)∆P=½ 1000 (32-12)∆P=4000 N/m2

Q158. When the length of a simple pendulum is doubled, find the ratio of the new frequency to the old frequency?

• A. 1/4
• B. 1/2
• C. √2
• D. 1/√2✓

Explanation: ‘T’ the period of a pendulum is given byT= 2π√ (l/g)Where,l is the length of the pendulumg is the acceleration due to gravity,Frequency ‘f’ is given as,f= 1/T = 1/2π √ (g/l)If we square on both sides,f2=[ 1/2π √ (g/l)]2f2= 1/4π . (g/l)Since in the given question l is now 2l hence l=2lThen, the new frequency will bef12= 1/4π . (g/2l)By dividing the squares of the new frequencies and original f12/f2f12/f2= [1/4π . (g/2l)] ÷ [1/4π . (g/l)]f1/f = 1 / √ 2

Q159. Isobaric processes occur at:

• A. Constant temperature
• B. Constant pressure✓
• C. Constant volume
• D. Constant temperature and constant pressure

Explanation: Isobaric process is a process in which the change in pressure is 0 i.e. pressure remains constant.Processes at constant volume are called ‘isochoric’.Processes at constant temperature are called ‘isothermal’. The word “iso” means same/constant and bar means pressure since we know that unit of pressure is bar.

Q160. The Coulomb's force between two point charges q1=1C and q2 is 2N. Where the distance between them is 3m, the charge q2 is:

• A. 1 x 10-9 C
• B. 1 x 109 C
• C. 2 x 10-9C✓
• D. 4 x 10-9 C

Explanation: From coulomb’s law we know F=Kq1q2/r² Rearranging the equation, we get: q2=Fxr²/Kxq1 =2x9/9x10⁹x1 =2x10-⁹C Ans

Q161. A 5 watt LED bulb converts 80% of the power into light photons wavelength 660 nm. What is the number of photons emitted from the bulb in one second.

• A. 5.8 x 1034
• B. 7.5 x 1018
• C. 6.6 x 107
• D. 1.3 x 1019✓

Explanation: Photon energy formula: E=hc/λ , where h is planck's constant λ =660nm c= 3*108 m/s h= 6.626 × 10-34 Js E=6.626*10-34 * 3*108 / 660*10-9 (Js*m/s/m = J) E=3.01*10-19J(per photon) Total energy= 1sec*5watt*80/100(efficiency) = 4 ws = 4J No. of photons = Total energy/E = 4J/3.01*10-19J = 1.3*1019

Q162. The consumption of energy by 60-watt bulb in 2 seconds is:

• A. 20 J
• B. 120 J✓
• C. 30 J
• D. 0.02 J

Explanation: Formula for power is[P=E/t]60=E/260×2=EE=120JOptions B is correct.

Q163. The principle of homogeneity of dimensions determines

• A. Only variable in the equation
• B. Only constant in the equation
• C. Correctness of an equation✓
• D. Constant and variable in the equation

Explanation: A is incorrect because principle of homogeneity of dimension does not determines the only variables of equationB is incorrect because principle of homogeneity of dimension does not determines only variables of equationC is correct since principle of homogeneity of dimension means the same dimensions on both sides of equation and it tells us about correctness of equation D is incorrect because principle of homogeneity of dimension does not tell us about constants and variables of equation

Q164. If a force of magnitude 8 N acts on a body in direction making an angle 30, its x and y components will be:

• A. Fx = 4√3 and Fy = 8
• B. Fx = 8 and Fy = 4√3
• C. Fx = 4√3 and Fy = 4✓
• D. Fx = 8√3 and Fy = 4

Explanation: x-component is given by Fx=F cosθFx=8×30 Fx=4√3The y-component is given byFy=F sinθFy=8×1/2Fy=4

Q165. If a force of 12 N acts on a car and changes its momentum from 36 kgm/sec to 60 kgm/sec, the time during which this change occurs will be

• A. 24 sec
• B. 2 sec✓
• C. 12 sec
• D. 8 sec

Explanation: GivenInitial momentum=36kgm/sFinal momentum=60kgm/s Applied force=12NRequired Time=?FormulaF×t=mvf-mvit=mvf-mvi/Ft=60-36/12t=2secResultThe time in which the change occurs will be 2sec.

Q166. A wheel of radius 1m covers an angular displacement of 180.Its linear displacement is:

• A. 3.14 m✓
• B. π rad
• C. 6.28 m
• D. 0.157 m

Explanation: A) is correctReasonGiven θ=180degree=π=3.14r=1mFormula:S=rθBy putting valuesS=1×3.14S=3.14mB)is incorrect because rad is not the unit of linear displacement.Metre is the correct unit.C) and D) are incorrect because the given values are not correct values. The answer should be 3.14m.

Q167. In the diagram below, the displacement of an oscillating particle is plotted against time. What does the length ‘PR’ on the time axis represent?

• A. Twice the frequency
• B. Half the period✓
• C. Half the frequency
• D. Twice the period

Explanation: The time period of the wave is the time between two consecutive troughs or two consecutive crests. In the given diagram you can see the distance between a trough and a crest which means its half a period.

Q168. What will be the effect on the capacitance of a capacitor if area of each plate is doubled while separation between the plates is halved?

• A. Capacitance remains same
• B. Capacitance becomes double
• C. Capacitance becomes four times✓
• D. Capacitance reduces to half

Explanation: The formula for capacitance is𝐶=ε𝐴 / 𝑑where,A is the area of the plate, d is the distance between the two parallel plates.If area is doubled, it becomes 2Aif distance is halved it becomes d/2So the new capacitance will be,𝐶2=ε2𝐴÷ 𝑑/2 = 4ε𝐴/𝑑Since 𝐶1 = ε𝐴/𝑑𝐶2= 4𝐶1Hence capacitance will become 4 times.

Q169. Arshad is driving down 7th street, he drives 150m in 18s.Assume he does not speed up or slow down, what is his speed:

• A. 0.38m/s
• B. 126m/s
• C. 8.33m/s✓
• D. 58.33m/s

Explanation: We need to calculate the constant speed, the formula for it is given as: speed= distance/time = 150/18 = 8.33m/s Hence the right answer is option C.

Q170. In the shown figure, calculate the total work done on the gas when it is transformed from state a to state c, along the path indicated?

• A. 1500 J
• B. 3000 J
• C. 4500 J✓
• D. 5000 J
• E. 9, 500 J

Explanation: The thermodynamic work done is W = PdVAs dV = 0 for path b to c it will not contribute any work.The work done will come from path a to b and the required work done,W = ( 3 x 105) x (25 - 10) 10-3 = 4500 J

Q171. What is the instantaneous power dissipated through a resistor of resistance 10 ohm if it is connected to an AC source of frequency 15 Hz at 1/180 sec if peak value is 20 V?

• A. 10 W✓
• B. 100 W
• C. 40 W
• D. Cannot be determined

Explanation: UsingVo = V sin(2𝜋ft) = 20 x sin (2𝜋 x 15 x 1/180) = 10 VUsingP = v2/ R = 102 / 10 = 10 W

Q172. Force is a derived quantity, its derived unit can be expressed in terms of the base units as:

• A. Kgms-2✓
• B. Kgcms-2
• C. Kgm2s2
• D. Kgms2

Explanation: Since F=ma where m: mass in kg a:acceleration in m/s2F = Kg ms-2 = newton

Q173. Coulomb's law is given by the formula: F=kq1 q2 / r2The magnitude of k having the unit of Nm2 C-2 for free space is equal to

• A. 9 x 107
• B. 6 x 107
• C. 10 x 109
• D. 9 x 109✓

Explanation: The Coulomb constant, the electric force constant, or the electrostatic constant (denoted ke, k or K) is a proportionality constant in electrostatics equations. In SI units it is equal to 8.9875517923(14)×109 (9*109)kg⋅m3⋅s−2⋅C−2

Q174. Which of the following gives the relationship between linear velocity and angular velocity?

• A. v = rω✓
• B. v = rθ
• C. v=sω
• D. v=sθ

Explanation: The greater the rotation angle in a given amount of time, the greater the angular velocity. Angular velocity ω is analogous to linear velocity v. We can write the relationship between linear velocity and angular velocity in two different ways: v=rω or ω=v/r.

Q175. If one mole of an ideal gas is heated at constant pressure, then the first law of thermodynamics can be written as:

• A. CpΔT = CvΔT + PΔV✓
• B. CvΔT = CpΔT + PΔV
• C. CpΔT = CvΔT + VΔP
• D. ΔCpT = ΔCvT + PΔV

Explanation: Heat supplied to the gas at constant pressure isΔQ=nCPΔTChange in internal energy,ΔU=nCVΔTChange in work done,ΔW = PΔVAccording to first law of thermodynamicsΔQ=ΔU+ΔWnCPΔT= nCVΔT + PΔV

Q176. Velocity of electron moving in first orbit of hydrogen is

• A. 2.19 x 107 m/sec
• B. 2.18 x 107 m/sec
• C. 2.2 x 108 m/sec
• D. 2.19 x 106 m/sec✓

Explanation: A, B and C are incorrect because the given values are not correct.D is correct since the velocity of an electron in the first Bohr orbit of H atommvr = nh/2πv = nh/2πmrv = (1 × 6.626×10−34)/ (2 × 3.14 × 9.1 × 0−31 × 0.529 × 10−10)v = 2.19×106 ms−1

Q177. If the velocity of the body changes by equal amount in equal intervals of time, the body is said to have:

• A. Variable acceleration
• B. Uniform acceleration✓
• C. Uniform velocity
• D. Negative acceleration

Explanation: When the velocity of the body changes by equal amounts in equal intervals of time,the body is said to have uniform acceleration.A)is incorrect because variable acceleration occurs when velocity of body changes by unequal amounts in unequal intervals of time.Unequal change in only velocity or time can cause variable acceleration.B)is correct according to definition.C)is incorrect because the change in velocity will cause acceleration.D)is incorrect because negative acceleration is due to slowing down of an object.

Q178. Which one of the following is a non-conservative force?

• A. Electric force
• B. Elastic spring force
• C. Gravitational force
• D. Frictional force✓

Explanation: Conservative forces are those forces which don't depend upon path followed but depend on the initial and final position.A,B and C are incorrect as they are conservative forces.D is correct because it depends upon the path followed.

Q179. An oscillating body is at mean position at t = 0. At t = T/4 it will be at:

• A. Extreme position✓
• B. Mean position
• C. Between extreme and mean position
• D. Beyond extreme position

Explanation: A)is correct because at T/4 and 3T/4,the body is at the extreme position.B)is incorrect because at time t=0,T/2 and T,the body is at the mean position.C)is incorrect because a body can't go beyond extreme position in Simple Harmonic Motion.

Q180. When the source of sound moves towards the stationary observer, the value of apparent frequency ‘fo’ is:

• A. Option A
• B. Option B✓
• C. Option C
• D. Option D

Explanation: When the source moves towards a stationary observer, the apparent frequency of sound increases by the Doppler Effect and is given byfo =( v / v - ui) . fWhere, ‘V’ is the velocity of the sound, ‘Ui’ is the velocity of the source of the sound and ‘f’ is the original frequency of the sound emitted by the source.

Q181. The relation ‘PV = nRT’ shows which law of physics:

• A. Charles Law
• B. Avogadro’s Law
• C. Newton’s Constant
• D. Ideal Gas Law✓

Explanation: The ideal gas law, also called the general gas equation, is the equation of state of a hypothetical ideal gas. It shows the relation between the pressure P, volume V, and temperature T of gas in the limit of low pressures and high temperatures, such that the molecules of the gas move almost independently of each other. In such a case, all gases obey an equation of state known as the ideal gas law: PV = nRT, where n is the number of moles of the gas and R is the universal (or perfect) gas constant.

Q182. Which relation exactly described the isothermal process?

• A. Q = W✓
• B. W = -ΔU
• C. Q = -ΔU
• D. Q = ΔU + W

Explanation: An isothermal process is a thermodynamic process in which the temperature of a system remains constant. The transfer of heat into or out of the system happens so slowly that thermal equilibrium is maintained. In an isothermal process ΔT=0. If ΔT=0 then we can say that ΔU=0. According to 1st law of thermodynamics Q= ΔU+W. In this case 1st law can be written as Q=W

Q183. Resistance between two opposite faces of square thin film of area 1 mm2 having thickness of 1 μm if resistivity of material is 10-6 Ω will be:

• A. 1000 Ω
• B. 100 Ω
• C. 1 Ω✓
• D. 10 Ω

Explanation: Given data Area, A= 1mm2 Resistivity, ρ= 10-6Ωm Thickness, x= 10-6m Now we have Resistance, R=ρl/A Where, A= length(l) x thickness(x) Thus, R= ρll.x Or R= ρ/x Subsituting the values , R= 10-6Ωm10-6m R= 1Ω

Q184. If general equation for destructive interference’s is given by the relation, Optic path difference = (m +½) λ where ‘m’ is an integer, then the first dark fringe which appears from ’m’ will be equal to:

• A. 23
• B. 12
• C. 0✓
• D. 1

Explanation: If general equation for destructive interference's is given by the relation, Optic path difference = (m+1/2) λ where 'm' is an integer, then first dark fringe appears from 'm' will be equal to 0 For destructive interference • m = 0 would give us the angle of the first order dark fringe • m = 1 would give us the second order fringe, etc. For both bright and dark fringes, the first order fringe is the one closest to the central maximum.

Q185. A wire is stretched by a force ‘F’ which causes an extension ∆l, the energy stored in the wire is:

• A. F∆l
• B. 2F∆l
• C. ½ F∆l2
• D. ½ F∆l✓

Explanation: Given that, force applied = F . extension = ∆l and we assume the length of the wire to be = L.If the elastic limit is not exceeded then the stress is directly proportional to strain.Where stress is the amount of force applied per unit area (σ = F/A)And strain is extension per unit length (ε = ∆l/l)Hence,Energy stored = ½ x stress x strain x volumeEnergy stored = ½ x (F/A) x (∆l/L) x A x LEnergy stored = ½ F∆l

Q186. A heat engine operating according to the second law of thermodynamics rejects one fourth of the heat taken from a high temperature reservoir. What is the percentage efficiency of a heat engine?

• A. 100%
• B. 25%
• C. 50%
• D. 75%✓

Explanation: The percentage efficiency of a heat engine is given by:Efficiency = (Useful work output / Heat input) x 100%According to the second law of thermodynamics, some heat must be rejected to a low temperature reservoir during the operation of a heat engine. Let Qh be the heat taken from a high temperature reservoir, and Qc be the heat rejected to a low temperature reservoir. The net work output of the engine is given by:W = Qh - QcGiven that the engine rejects one-fourth of the heat taken from the high temperature reservoir, we can write:Qc = Qh/4Substituting this in the above equation for W, we get:W = Qh - Qh/4 = 3Qh/4The efficiency of the engine is therefore:Efficiency = (W / Qh) x 100%Efficiency = [(3Qh/4) / Qh] x 100%Efficiency = 75%Therefore, the correct option is D) 75%.

Q187. ‘F’ is maximum force acting on a conductor. Now if we change the direction of conductor by making an angle of 45° with the magnetic field then the force becomes:

• A. F/2
• B. 2F
• C. F/√2✓
• D. √2 F

Explanation: As we know that force experienced by the current carrying conductor is given by F'=IBLsinθ If θ= 45o F'=Fsin45° F'=F(0.707) F'=F/√2

Q188. The ratio of displacement along diameter of circle and total distance along circle is:

• A. 1:π✓
• B. π:1
• C. 2:π
• D. Π:2

Explanation: Since the diameter of the circle is unknown, we can assume it to be 2r where ‘r’ is the radius of the circle. The total distance along the circle refers to the circumference of the circle which, mathematically is, 2πr. The ratio of the two values would be 2r:2πr which can be simplified to 1:π.

Q189. In mass spring system mass 'm' is attached with spring of spring constant 'k' with time period 'T1'..Then the mass is replaced by '2m' with same spring, what is the time period 'T2'

• A. T2=T1
• B. T2=2T1
• C. T2=√2T1✓
• D. T2=T1/(√2)

Explanation: Time period T for a mass attached to a spring can be calculated by using the following formula: T=2𝝅√m/k T1=2𝝅√m/k ==============eq(1) Since 2m is attached to the same spring to which m was attached, spring constant k remains same. T2=2𝝅√2m/k ==============eq(2) Divide eq(2) by eq(1) T2/T1=2𝝅√2m/k / 2𝝅√m/k T2=√2xT1 So increasing the mass by 2 would increase the time period by √2 Correct answer here is option C

Q190. A wire of resistance 4Ω is bent in the form of a circle. The resistance between the ends of any diameter is:

• A. 1 Ω✓
• B. 2 Ω
• C. 4 Ω
• D. 8 Ω

Explanation: In forming a ring and measuring the resistance across the diameter, we divided the length of the wire in half. If the whole wire before we bent it is 4 ohms, then each half considered by itself is 2 ohms. What this then means is that we’ve reduced this to two 2-ohm resistances in parallel. According to the formula for resistances in parallel: 1/R AB = 1/R1 + 1/R2 = 2/2R = 1/R Or RAB = 1 ohm is our answer.

Q191. A block moves in uniform circular motion because a cord tied to the block is anchored at the centre of a circle. Then the power of the force exerted on the block by the cord is:

• A. Positive
• B. Negative
• C. Zero✓
• D. Infinite

Explanation: Correct option is C. F and v are perpendicular.Power = Force x v = FVcos90 = Zero

Q192. I. Ms. Kulsoom labelled Mr. Waleed a deserter.II. Ms. Kulsoom offered an apology.

• A. Statement I is the cause and statement II is its effect.✓
• B. Statement II is the cause and statement I is its effect
• C. Both statements I and II are independent causes
• D. Both statements I and II are the effects of independent cause.

Explanation: The best way to tackle cause and effect questions is to try to merge the two sectences into one using the format: "sentence 1...As a result,...sentence 2. If the new sentence makes sense, then sentence one is the cause and sentence 2 is the effect. So in this case, we could rewrite the two sentences as:"Ms. Kulsoom labelled Mr. Waleed a deserter. As a result, Ms. Kulsoom offered an apology." This makes sense. She did something wrong and as a result she is apologising. Hence we can say that sentence 1 is the cause, and sentence 2 is the effect.

Q193. Children are in pursuit of a dog whose leash has broken. James is directly behind the dog. Ruby is behind James. Rachel is behind Ruby. Max is ahead of the dog walking down the street in the opposite direction. As the children and dog pass, Max turns around and joins the pursuit. He runs in behind Ruby. James runs faster and is alongside the dog on the left. Ruby runs faster and is alongside the dog on the right. Which child is directly behind the clog?

• A. James
• B. Ruby
• C. Rachel
• D. Max✓

Explanation: After all the switches were made, Max is directly behind the dog, James is alongside the dog on the left, Ruby is alongside the dog on the right, and Rachel is behind Max.

Q194. Dependent Causes/ Independent Causes: I. PTI was not satisfied with the election results of Sindh assembly, when it did not get a single seat. II. PTI has replaced the chief minister of Sindh.

• A. Statement I is the cause and statement II is its effect.
• B. Statement II is the cause and statement I is its effect.
• C. Both statements I and II are independent causes.
• D. Both statements I and II are the effects of independent cause.✓

Explanation: In this scenario, both statements I and II are outcomes that are not directly dependent on each other. They are the effects of an independent cause. The dissatisfaction of PTI with the election results in Sindh assembly by-elections (statement I) and the replacement of the chief minister of Sindh by PTI (statement II) are separate events that may be influenced by different factors or decisions within the political context.

Q195. Only one meaningful word can be formed by rearranging the letters of the given jumbled word. Find out that word. MUSPOPAPOTIH

• A. METAMORPHIC
• B. PHILANTHROPIST
• C. HIPPOCAMPUS
• D. HIPPOPOTAMUS✓

Explanation: Count the number of letters of the word given in the question and then corroborate it with the options.

Q196. Asiya goes 30 km towards North from a fixed point, then after turning to her right she goes another 15 km. Then she takes another right and goes 30km. How far and in what direction is she from her starting point?

• A. 10 km east
• B. 15 km east✓
• C. 20 km east
• D. 25 km east

Explanation: Option B is correct. In reference to the given image her current position is 15km East from the point where she started.

Q197. I. Car manufacturing companies have recently increased the prices of mid-sized cars. II.The Government recently increased the duty on mid-sized cars.

• A. Statement I is the cause and statement II is its effect
• B. Statement II is the cause and statement I is its effect✓
• C. Both the statements I and II are independent
• D. Both the statements I and 11 are effects of so

Explanation: Is correct as the government increased the duty on mid sized cars which is the cause due to which the companies have increased the prices of mid sized cars which is the effect