EMBRYOLOGY
CHROMOSOMES AND CELL DIVISIONS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Chromosomes line up in middle of cell
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Chromatids are pulled apart
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Chromosomes make a copy
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Chromosomes disappear
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Detailed explanation-1: -Throughout interphase, nuclear DNA remains in a semi-condensed chromatin configuration. In the S phase (synthesis phase), DNA replication results in the formation of two identical copies of each chromosome-sister chromatids-that are firmly attached at the centromere region.
Detailed explanation-2: -After DNA replication, each chromosome now consists of two physically attached sister chromatids. After chromosome condensation, the chromosomes condense to form compact structures (still made up of two chromatids).
Detailed explanation-3: -During interphase (1), chromatin is in its least condensed state and appears loosely distributed throughout the nucleus. Chromatin condensation begins during prophase (2) and chromosomes become visible. Chromosomes remain condensed throughout the various stages of mitosis (2-5).