Which of the following is the longest phase of the cell cycle?
- A.Prophase
- B.Interphase
- C.Metaphase
- D.Telophase
Correct answer
Explanation
The correct answer is B, interphase. Interphase occupies more than ninety-five per cent of the duration of the cell cycle, because in it the cell must grow to a sufficient size, synthesise proteins and RNA, duplicate its entire DNA and prepare the structures needed for division. It is divided into G1, S and G2, and it is sometimes wrongly called the resting stage although the cell is in fact extremely active throughout. In a human cell with a cycle of about twenty-four hours, the actual division takes only about one hour. A, prophase is the longest stage within mitosis itself but is a small part of the whole cycle. C, metaphase is brief, the chromosomes merely coming into line. D, telophase is also brief, being the reversal of the events of prophase.
Read the full article: Cell Division: Mitosis and Meiosis Explained for Exams
Practice Questions
View allIn which phase of the cell cycle does DNA replication take place?
- A.G1 phase
- B.S phase
- C.G2 phase
- D.M phase
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During this phase the DNA of the cell is copied so that the amount of DNA in the nucleus doubles, while the number of chromosomes remains unchanged because each chromosome now simply consists of two identical sister chromatids joined at the centromere.
Read the full explanation →Mitosis is called the equational division because
- A.it produces four daughter cells
- B.the chromosome number of the daughter cells is the same as that of the parent cell
- C.it halves the chromosome number
- D.it occurs only in reproductive cells
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In mitosis each centromere splits in anaphase and one chromatid of every chromosome goes to each pole, so the two daughter cells receive exactly the same number of chromosomes as the parent cell had, and exactly the same genetic information.
Read the full explanation →At which stage of mitosis do the chromosomes line up at the equator of the cell?
- A.Prophase
- B.Metaphase
- C.Anaphase
- D.Telophase
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In this stage the condensed chromosomes, each consisting of two sister chromatids, are moved by the spindle fibres until their centromeres lie in one plane across the middle of the cell, known as the metaphase plate or equatorial plate.
Read the full explanation →The splitting of the centromere and the movement of sister chromatids to opposite poles occurs in
- A.prophase
- B.metaphase
- C.anaphase
- D.telophase
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Once the chromosomes are aligned on the metaphase plate and every kinetochore is attached to a spindle fibre, the centromere holding the two sister chromatids together splits.
Read the full explanation →Cytokinesis in a plant cell differs from that in an animal cell because
- A.a cleavage furrow forms in the plant cell
- B.a cell plate forms in the plant cell
- C.the plant cell does not divide its cytoplasm
- D.the plant cell divides its nucleus twice
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An animal cell divides its cytoplasm by a cleavage furrow, in which the plasma membrane is pulled inward around the middle until the cell is pinched into two.
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