CELL DIVISION
CELL DIVISION AND CANCEROUS CELLS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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a. just after cytokinesis through the end of G1
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b. just after metaphase through telophase
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c. just after S phase through separation in metaphase
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during all of Interphase
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Detailed explanation-1: -The centromere holding the sister chromatids splits and the chromatids separate. These separated chromatids are pulled to opposite poles by spindle fibres. This occurs during anaphase. Q.
Detailed explanation-2: -Metaphase leads to anaphase, during which each chromosome’s sister chromatids separate and move to opposite poles of the cell. Enzymatic breakdown of cohesin-which linked the sister chromatids together during prophase-causes this separation to occur.
Detailed explanation-3: -During S phase, which follows G1 phase, all of the chromosomes are replicated. Following replication, each chromosome now consists of two sister chromatids (see figure below).
Detailed explanation-4: -Cell division occurs during M phase, which consists of nuclear division (mitosis) followed by cytoplasmic division (cytokinesis). The DNA is replicated in the preceding S phase; the two copies of each replicated chromosome (called sister chromatids) remain glued together by cohesins.