CELL DIVISION
THE CELL CYCLE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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G2 Phase
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Mitosis Phase
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All Phases
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S Phase
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G2 Phase
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Detailed explanation-1: -Giemsa staining has been used for identifying individual human chromosomes. Giemsa-dark and-light bands generally are thought to correspond to GC-poor and GC-rich regions; however, several experiments showed that the correspondence is quite poor.
Detailed explanation-2: -A karyotype is the number and appearance of chromosomes, and includes their length, banding pattern, and centromere position. To obtain a view of an individual’s karyotype, cytologists photograph the chromosomes and then cut and paste each chromosome into a chart, or karyogram, also known as an ideogram (Figure 1).
Detailed explanation-3: -Typically, Giemsa staining produces between 400 and 800 bands distributed among the 23 pairs of human chromosomes. Measured in DNA terms, a G-band represents several million to 10 million base pairs of DNA, a stretch long enough to contain hundreds of genes.
Detailed explanation-4: -Chromosomes are visualized using Giemsa staining (G-banding). Light bands represent early replicating regions, rich in guanine and cytosine nucleotides. Dark bands represent late replicating regions, rich in adenine and thymine nucleotides.