EMBRYOLOGY
CHROMOSOMES AND CELL DIVISIONS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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chromatin
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gene
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chromosome
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chromatid
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centromere
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Detailed explanation-1: -A sister chromatid refers to the identical copies (chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere. In other words, a sister chromatid may also be said to be ‘one-half’ of the duplicated chromosome. A pair of sister chromatids is called a dyad.
Detailed explanation-2: -Chromosomes have proteins called histones that bind to DNA. DNA has two strands that twist into the shape of a spiral ladder called a helix. DNA is made up of four building blocks called nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C).
Detailed explanation-3: -Each chromatid will have two strands of DNA, resulting in four strands of DNA (or two DNA molecules) on the chromosome during the cell division.