All Free Biology MCQs with Answers
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19844 questions · page 581 of 1985
5801. Separation of homologous chromosomes occurs during:
- A. Prophase
- B. Anaphase
- C. Metaphase
- D. Telophase
Explanation: Anaphase I of meiosis separates homologous chromosomes while sister chromatids remain together.
Correct answer: Anaphase5802. The stage of mitosis or meiosis during which the microtubules become organized into a spindle and the chromosomes come to lie in the spindle's equatorial plate is called:
- A. Prophase
- B. Metaphase
- C. Anaphase
- D. Telophase
Explanation: In metaphase, spindle fibers attach to centromeres and chromosomes align at the metaphase plate.
Correct answer: Metaphase5803. "All cells come from the Pre-existing cell". This statement was proposed by:
- A. Rudolph Virchow
- B. F. Griffith
- C. Watson & Crick
- D. Hershey & Chase
Explanation: Rudolf Virchow stated "Omnis cellula e cellula" in 1855, meaning all cells arise from pre-existing cells.
Correct answer: Rudolph Virchow5804. Each round of cell growth and division is called:
- A. Growth Curve
- B. Cell Cycle
- C. Cell Growth Hypothesis
- D. One Gene - One Enzyme Hypothesis
Explanation: The cell cycle includes cell growth, DNA replication, mitosis. and cytokinesis.
Correct answer: Cell Cycle5805. The non‑dividing phase at the beginning of the cell cycle is called:
- A. Interphase
- B. Prophase
- C. G-0 Phase
- D. G-1 Phase
Explanation: Interphase is the resting phase where the cell grows, duplicates DNA, and prepares for division.
Correct answer: Interphase5806. The phase of Interphase where no DNA synthesis occurs is:
- A. G-0 Phase
- B. G-1 Phase
- C. S Phase
- D. Both A and B
Explanation: DNA synthesis occurs only in S phase; G-1 and G-0 do not involve DNA replication.
Correct answer: Both A and B5807. Cells remain viable and metabolically active but do not divide in sub-stage:
- A. G-0 Phase
- B. G-1 Phase
- C. S Phase
- D. Mitotic Phase
Explanation: G-0 phase cells are metabolically active but have exited the cell cycle.
Correct answer: G-0 Phase5808. DNA synthesis takes place in sub-stage:
- A. G-0 Phase
- B. G-1 Phase
- C. S Phase
- D. Mitotic Phase
Explanation: S phase is when DNA replication occurs, forming identical sister chromatics.
Correct answer: S Phase5809. In the cell cycle, the most variable sub-stage is:
- A. G-0 Phase
- B. G-1 Phase
- C. G-2 Phase
- D. S Phase
Explanation: G-1 phase duration varies among cells; some quickly enter S phase, others stay longer or enter G-0.
Correct answer: G-1 Phase5810. Interphase consists of following sub-stages, the correct sequence is:
- A. G-1, G-2, S
- B. S, G-1, G-2
- C. G-1, S, G-2
- D. G-2, S, G-1
Explanation: Interphase sequence: G-1 (growth)--->S (DNA replication) --->G-2 (preparation for mitosis).
Correct answer: G-1, S, G-2