Question

The quantity of DNA in a chromosome at metaphase is :

• A. One in mitosis and two in meiosis
• B. Two in mitosis and four in meiosis
• C. Two each in meiosis and mitosis
• D. Two in mitosis and one in meiosis

Answer 1

The correct option is C Two each in meiosis and mitosis

A chromosome in G1 of the cell cycle is composed of a very long molecule of double stranded DNA. Recall that DNA is replicated during the S phase of the cell cycle. Thus during metaphase of mitosis, each chromosome (i.e., each chromatid pair) will contain two molecules of double stranded DNA (one molecule per sister chromatid).


During prophase I and metaphase I of meiosis, a chromosome consists of a tetrad (4 chromatids or 4 DNA molecules) and is reduced to two chromatids (2 DNA molecules) by the time metaphase II occurs.


Thus, the correct answer is "option A"