THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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sister chromatids
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homologous chromosomes
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centrioles
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Detailed explanation-1: -Definition. 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: -Definition. Following DNA replication, as part of cell division, each chromosome consists of two full length DNA molecules joined at the centromere. These two DNA molecules are sister chromatids.
Detailed explanation-3: -Following DNA replication (middle panels) “Watson” and Crick“ DNA template strands are copied to yield two sister chromatids with identical DNA sequence.
Detailed explanation-4: -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-5: -The sister chromatids are pairs of identical copies of DNA joined at a point called the centromere. Then, a structure called the mitotic spindle begins to form. The mitotic spindle is made of long proteins called microtubules that begin forming at opposite ends of the cell.