CELL STRUCTURES AND FUNCTION
CELL CYCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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centromeres
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sister chromatids
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spindle
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tissues
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Detailed explanation-1: -A chromatid is one of the two identical halves of a chromosome that has been replicated in preparation for cell division. The two “sister” chromatids are joined at a constricted region of the chromosome called the centromere.
Detailed explanation-2: -After replication there are a total of 92 sister chromatids in each cell. There are 46 individual chromosomes in each cell. Metaphase: During metaphase, each of the 46 chromosomes line up along the center of the cell at the metaphase plate.
Detailed explanation-3: -A pair of sister chromatids is called a dyad.
Detailed explanation-4: -The sister chromatids are identical to one another and are attached to each other by proteins called cohesins. The attachment between sister chromatids is tightest at the centromere, a region of DNA that is important for their separation during later stages of cell division.
Detailed explanation-5: -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 (Figure 9.16B).