Self Assessment Test 1 Cell Cycle

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Self Assessment Test 1 Cell Cycle B.Sc. (H) Zoology Sem II Paper: Cell Biology Self Assessment Test Cell cycle and its regulation Teacher: Dr. Anjali S. Nawani Dated: April25, 2002 Q1. A cell cycle consist is a co-ordinated process of a) Cell growth b) DNA Replication c) Distribution of chromosomes to daughter nuclei d) Cell division e) All of the above Q2. In Prokaryotes, cell growth and DNA replication take place throughout most of the cell cycle. a) True b) False Q3. In eukaryotes, cell divides in approx. a) 24hrs b) 12hrs c) 8hrs d) 2hrs. Q4. Microscopic view of cell cycle is divided into mitosis and interphase. a) True b) False Q5. The cell undergo the process of cell division only for………time of a cell cycle, rest of the time it stays in interphase. a) 1% b) 2% c) 5% d) 10% Q6. In eukaryotes, the cell cycle consists of four discrete G1, S , G2 and M phases. a) True b) False Q7. The gap (interval) between mitosis and initiation of DNA synthesis is termed as a) G1 phase b) G2 phase c) G0 phase d) S phase Q8. During G1 phase of the cell cycle a) the cell is metabolically active b) the cell continuously grows c) DNA replication takes place d) both a) and b) Q9. DNA Synthesis takes place during which of the following phase/s of the cell cycle a) G phase b) S phase c) G2 phase d) both a) and b) Q10. During G2 phase of the cycle a) Cell growth continues b) Proteins are synthesised in preparation of mitosis c) DNA synthesis takes place d) both a) and b) Q11. Which is the longest phase of cell cycle a) G1 b) S c) G2 d) M Q12. The restriction point (R), also known as G1/S checkpoint, is a cell cycle checkpoint in the G1 phase of the animal cell cycle at which the cell becomes "committed" to the cell cycle, and after which extracellular signals are no longer required to stimulate proliferation. a) True b) False Q12. The regulatory point in G1 phase of Yeast cell cycle is called a) START b) G0 phase c) both of the above d) None of the above Q13. The restriction point in G1 phase of animal cells is called a) START b) G0 phase c) both of the above d) None of the above Q14. During G0 phase, the cell is metabolically active with reduced rate of protein synthesis but stops to grow. a) True b) False Q15. Which of the following cells in our body are arrested at G0 phase of the cell cycle a) Skin fibroblast cells b) Neuronal cells c) Cardiac muscle cells d) All of the above Q16. Although the proliferation of most cells is regulated primarily in G1, some cycles are instead controlled principally in G2. a) True b) False Q17. In oocyte, until fertilisation cell cycle is restricted at a) G0 phase b) G1 phase c) S phase d) G2 phase Q18. How many major checkpoints are there to regulate cell cycle? a) one b) two c) three d) four Q19. The G1/S checkpoint (Go phase), DNA damage checkpoint and spindle assembly checkpoint regulates the cell cycle. a) True b) False Q20. DNA damage checkpoint functions to ensure that damaged DNA is not replicated and passed on to daughter cells. a) True b) False Q21. DNA damage checkpoint function during a) G1 phase b) G2 phase c) S phase d) All of the above Q22. Spindle assembly checkpoint monitors the alignment of chromosomes on the mitotic spindle, thus ensuring that a complete set of chromosomes is distributed accurately to the daughter cells. a) True b) False Q23. Spindle assembly checkpoint function during a) G1 phase b) G2 phase c) S phase d) M Phase Q24. Which of the following checkpoints ensures/restricts DNA replication once per cycle a) G1/S checkpoint b) DNA damage checkpoint c) Spindle assembly checkpoint d) All of the above Answer Key Q1 (e) Q2 (a) Q3 (a) Q4 (a) Q5 (c) Q6 (a) Q7 (a) Q8 (d) Q9 (b) Q10 (d) Q11 (a) Q12 (a) Q13 (a) Q14 (b) Q15 (d) Q16 (a) Q17 (d) Q18 (c) Q19 (a) Q20 (a) Q21 (d) Q22 (a) Q23 (c) Q24 (d).
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