Match the following scientists with their specific contributions: Column-I Column-II A. Griffith (i) — NEET Chemistry Past Papers Chemistry Question

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Match the following scientists with their specific contributions: Column-I Column-II A. Griffith (i) Demonstrated semiconservative replication of DNA B. Avery, MacLeod and McCarty (ii) Identified DNA as genetic material using bacteriophages C. Hershey and Chase (iii) Transformation experiment in bacteria D. Meselson and Stahl (iv) Proved DNA is transforming principle using enzymes (A) A-(iii), B-(iv), C-(ii), D-(i) (B) A-(iv), B-(iii), C-(ii), D-(i) (C) A-(iii), B-(ii), C-(iv), D-(i) (D) A-(ii), B-(iv), C-(iii), D-(i) 100. A DNA molecule has 30% adenine. What is the percentage of cytosine in the molecule? (1) 20% (2) 30% (3) 40% (4) 60% 101. Which of the following statements are correct regarding transcription and translation? A. The template strand of DNA is read in 3′ → 5′ direction. B. RNA polymerase synthesises RNA in 5′ → 3′ direction. C. Translation begins when the large ribosomal subunit binds mRNA. D. Untranslated regions (UTRs) are present at both 5′ and 3′ ends of mRNA. (1) A, B and D only (2) A and C only (3) B, C and D only (4) All of the above 102. Which of the following statements are correct regarding mutations? A. Point mutation involves change in a single base pair. B. Frameshift mutation results from insertion or deletion of nucleotides. C. All mutations are harmful and lethal. D. Mutation is a source of genetic variation. (1) A, B and D only (2) A and C only (3) B, C and D only (4) All of the above 103. Which of the following statements are correct regarding chromosomal theory of inheritance? A. Genes are located on chromosomes. B. Chromosomes segregate during meiosis leading to separation of alleles. C. Genes on different chromosomes always show linkage. D. Behaviour of chromosomes parallels behaviour of genes. (1) A, B and D only (2) A and C only (3) B, C and D only (4) All of the above MAJOR TEST SERIES - 1 9610ZMD800101250011 104. Assertion (A): In a dihybrid cross involving linked genes, the phenotypic ratio deviates from 9:3:3:1. Reason (R): Linked genes located on the same chromosome are always inherited together and never show recombination. (1) Both (A) and (R) are correct and (R) is the correct explanation of (A) (2) Both (A) and (R) are correct but (R) is not the correct explanation of (A) (3) (A) is correct but (R) is incorrect (4) (A) is incorrect but (R) is correct 105. Which population growth model is limited by environmental resistance? (1) Exponential (2) Logistic (3) Zero-growth (4) Declining population 106. Two species occupy the same niche. Over time, one disappears. This is an example of: (1) Mutualism (2) Resource partitioning (3) Competitive exclusion (4) Predation 107. A population with a large proportion of young individuals will: (1) Decline immediately (2) Grow rapidly in the future (3) Remain stable (4) Go extinct 108. Assertion (A): Net Primary Productivity (NPP) = GPP – Respiration. Reason (R): NPP represents energy available for consumers. (1) Both A and R true, R explains A (2) Both A and R true, R does not explain A (3) A true, R false (4) A false, R true 109. Which statements correctly identify: P. Detritus food chain starts with dead organic matter Q. Grazing food chain starts with producers R. Decomposers chemically break down detritus S. Detritivores physically fragment detritus (1) P and Q (2) P, Q and S (3) Only P (4) All are correct