Question 1

Q1. The enzyme that relieves supercoiling ahead of replication fork is:

Accepted Answer

Option C: Topoisomerase. Topoisomerase (DNA gyrase in prokaryotes) prevents excessive coiling during DNA unwinding.

Question 2

Q2. The site of protein synthesis in a cell is:

Accepted Answer

Option B: Ribosome. Ribosomes translate mRNA into polypeptide chains.

Question 3

Q3. In humans, sex of a child is determined by:

Accepted Answer

Option B: Sperm only. Sperm carries X or Y chromosome determining sex.

Question 4

Q4. Which of the following is a pyramidal structure always upright?

Accepted Answer

Option C: Pyramid of energy. Energy decreases at each trophic level due to loss as heat.

Question 5

Q5. Which antibody is responsible for primary immune response?

Accepted Answer

Option C: IgM. IgM is the first antibody produced during initial infection.

Question 6

Q6. A test cross helps in determining:

Accepted Answer

Option B: Genotype of dominant phenotype. Crossing with homozygous recessive reveals genotype of dominant individual.

Question 7

Q7. During meiosis, independent assortment occurs at:

Accepted Answer

Option B: Metaphase I. Random orientation of homologous chromosomes occurs in metaphase I.

Question 8

Q8. In ecological succession, pioneer species are usually:

Accepted Answer

Option C: Lichens. Lichens are first colonizers in barren environments.

Question 9

Q9. Which enzyme cuts DNA at specific recognition sequences?

Accepted Answer

Option B: Restriction endonuclease. Restriction enzymes recognize palindromic sequences and cut DNA.

Question 10

Q10. The process of copying DNA into RNA is called:

Accepted Answer

Option C: Transcription. RNA is synthesized from DNA template during transcription.

Question 11

Q11. Copper-T prevents pregnancy mainly by:

Accepted Answer

Option B: Blocking implantation. It creates an environment that prevents fertilized egg implantation.

Question 12

Q12. HIV primarily infects:

Accepted Answer

Option C: CD4+ T cells. HIV destroys helper T cells, weakening immunity.

Question 13

Q13. Only 10% of energy is transferred between trophic levels because:

Accepted Answer

Option B: Most energy is lost as heat. Respiration and metabolic activities dissipate energy as heat.

Question 14

Q14. Assertion (A): DNA replication is semiconservative. Reason (R): Each daughter DNA has one parental and one newly synthesized strand.

Accepted Answer

Option A: Both true and R explains A. Meselson-Stahl experiment confirmed semiconservative replication.

Question 15

Q15. Assertion (A): Genetic drift is strongest in large populations. Reason (R): Random changes have greater effect in small populations.

Accepted Answer

Option B: A false R true. Genetic drift significantly affects small populations, not large ones.

Question 16

Q16. Case Study: A patient has high blood glucose levels, frequent urination, and excessive thirst. What is the most likely condition?

Accepted Answer

Option A: Diabetes mellitus. Insulin deficiency leads to uncontrolled glucose levels.

Question 17

Q17. Case Study: Bt cotton shows resistance against insect pests. This resistance is due to:

Accepted Answer

Option B: Cry toxin gene expression. Bt gene produces Cry toxin lethal to specific insects.

Question 18

Q18. If recombination frequency between two genes is 50%, they are:

Accepted Answer

Option C: On different chromosomes or far apart. 50% recombination indicates independent assortment.

Question 19

Q19. In Hardy-Weinberg equilibrium, if p = 0.8, q =:

Accepted Answer

Option A: 0.2. p + q = 1 → q = 0.2

Question 20

Q20. Highest biodiversity is found in:

Accepted Answer

Option C: Tropical rainforest. Stable climate and high productivity support maximum biodiversity.

Mock Test 07 Performance Solutions

Detailed Question Analysis

Q1. The enzyme that relieves supercoiling ahead of replication fork is:

Q2. The site of protein synthesis in a cell is:

Q3. In humans, sex of a child is determined by:

Q4. Which of the following is a pyramidal structure always upright?

Q5. Which antibody is responsible for primary immune response?

Q6. A test cross helps in determining:

Q7. During meiosis, independent assortment occurs at:

Q8. In ecological succession, pioneer species are usually:

Q9. Which enzyme cuts DNA at specific recognition sequences?

Q10. The process of copying DNA into RNA is called:

Q11. Copper-T prevents pregnancy mainly by:

Q12. HIV primarily infects:

Q13. Only 10% of energy is transferred between trophic levels because:

Q14. Assertion (A): DNA replication is semiconservative. Reason (R): Each daughter DNA has one parental and one newly synthesized strand.

Q15. Assertion (A): Genetic drift is strongest in large populations. Reason (R): Random changes have greater effect in small populations.

Q16. Case Study: A patient has high blood glucose levels, frequent urination, and excessive thirst. What is the most likely condition?

Q17. Case Study: Bt cotton shows resistance against insect pests. This resistance is due to:

Q18. If recombination frequency between two genes is 50%, they are:

Q19. In Hardy-Weinberg equilibrium, if p = 0.8, q =:

Q20. Highest biodiversity is found in:

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Mock Test 07 Performance Solutions

Detailed Question Analysis

Q1. The enzyme that relieves supercoiling ahead of replication fork is:

Q2. The site of protein synthesis in a cell is:

Q3. In humans, sex of a child is determined by:

Q4. Which of the following is a pyramidal structure always upright?

Q5. Which antibody is responsible for primary immune response?

Q6. A test cross helps in determining:

Q7. During meiosis, independent assortment occurs at:

Q8. In ecological succession, pioneer species are usually:

Q9. Which enzyme cuts DNA at specific recognition sequences?

Q10. The process of copying DNA into RNA is called:

Q11. Copper-T prevents pregnancy mainly by:

Q12. HIV primarily infects:

Q13. Only 10% of energy is transferred between trophic levels because:

Q14. Assertion (A): DNA replication is semiconservative. Reason (R): Each daughter DNA has one parental and one newly synthesized strand.

Q15. Assertion (A): Genetic drift is strongest in large populations. Reason (R): Random changes have greater effect in small populations.

Q16. Case Study: A patient has high blood glucose levels, frequent urination, and excessive thirst. What is the most likely condition?

Q17. Case Study: Bt cotton shows resistance against insect pests. This resistance is due to:

Q18. If recombination frequency between two genes is 50%, they are:

Q19. In Hardy-Weinberg equilibrium, if p = 0.8, q =:

Q20. Highest biodiversity is found in:

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