本题目来源于试卷: Continuity and Change D.8 Inheritance，类别为 IB生物学
[单选题]
When does the random orientation of s) (obkc4ygq+ homgf(s0z:zccn5a*b )2uth 9xxt ologous chromosome pairs occur?
A. Metaphase I
B. Prophase I
C. Metaphase II
D. Prophase II
参考答案: A
本题详细解析:
Choice A is correct because during metaphase I homologous chromosomes align at the equator and are subject to random orientation. Choice B is incorrect as, during Prophase I, homologous chromosomes condense and crossing over occurs. Choice C is incorrect as, during Metaphase II, chromosomes align on the cell's equator, and there is random orientation of the sister chromatids and not homologous chromosomes. Choice D is incorrect as, during Prophase II, chromosomes align on the cell's equator.
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