Phases of the cell cycle and its checkpoints — NEET & JEE Questions

Question 1 · difficulty L1 · recall

The phase of the cell cycle in which DNA replication occurs is

• A. S phase
• B. G1 phase
• C. G2 phase
• D. M phase

Question 2 · difficulty L2 · understanding

Why is G1 considered a major growth phase?

• A. The cell grows and synthesises RNA and proteins before DNA replication
• B. Chromosomes separate to opposite poles
• C. DNA is replicated twice
• D. Cytokinesis occurs throughout G1

Question 3 · difficulty L2 · understanding

The G2 phase mainly prepares the cell for

• A. mitosis
• B. DNA replication for the first time
• C. fertilisation
• D. meiosis only

Question 4 · difficulty L2 · understanding

A cell-cycle checkpoint is important because it can

• A. delay progression when DNA is damaged or replication is incomplete
• B. guarantee mutation in every cell
• C. remove all chromosomes
• D. replace mitosis with meiosis

Question 5 · difficulty L3 · understanding

$$\text { Match List I with List II : }$$ List-I (Phase of cell cycle) List-II (Activity) A. $\mathrm{G}_1$ phase I. Actual cell division occurs B. S phase II. Cell is metabolically active and continuously grows but does not replicate its DNA C. $\mathrm{G}_2$ Phase III. Synthesis of DNA occurs and the amount of DNA per cell doubles D. M phase IV. Proteins are synthesized while cell growth continues Choose the correct answer from the options given below :

• A. A-IV, B-I, C-II, D-III
• B. A-I, B-II, C-III, D-IV
• C. A-III, B-IV, C-I, D-II
• D. A-II, B-III, C-IV, D-I

Question 6 · difficulty L3 · understanding

Match List-I with List-II : List - I List - II (A) Metacentric chromosome (I) Chromosome has a terminal centromere (B) Sub-metacentric chromosome (II) Middle centromere forming two equal arms of chromosome (C) Acrocentric chromosome (III) Centromere is slightly away from the middle of chromosome resulting into two unequal arms (D) Telocentric chromosome (IV) Centromere is situated close to its end forming one extremely short and one very long arm Choose the correct answer from the options given below:

• A. A-II, B-I, C-IV, D-III
• B. A-IV, B-I, C-II, D-III
• C. A-I, B-II, C-III, D-IV
• D. A-II, B-III, C-IV, D-I

Question 7 · difficulty L3 · understanding

Match List-I with List-II. List - I List - II (A) Cells are metabolically active and proliferate (I) G$$_2$$ phase (B) DNA replication takes place (II) G$$_1$$ phase (C) Proteins are synthesised (III) G$$_0$$ phase (D) Quiescent stage with metabolically active cells (IV) S phase Choose the correct answer from the options given below:

• A. A-IV, B-II, C-III, D-I
• B. A-I, B-III, C-IV, D-II
• C. A-I, B-I, C-III, D-IV
• D. A-II, B-IV, C-I, D-III

Question 8 · difficulty L3 · understanding

Following are the stages of cell division : A. Gap 2 phase B. Cytokinesis C. Synthesis phase D. Karyokinesis E. Gap 1 phase Choose the correct sequence of stages from the options given below :

• A. C-E-D-A-B
• B. E-B-D-A-C
• C. B-D-E-A-C
• D. E-C-A-D-B

Question 9 · difficulty L3 · understanding

Which one of the following is the quiescent stage of cell cycle?

• A. M
• B. G$$_2$$
• C. G$$_1$$
• D. G$$_0$$

Question 10 · difficulty L3 · understanding

Among eukaryotes, replication of DNA takes place in :

• A. S phase
• B. G 1 phase
• C. G 2 phase
• D. M phase