本题目来源于试卷: Continuity and Change D.4 Cell & Nuclear Division，类别为 IB生物学
[单选题]
Which statement(s) are trg7i9q 0hyth574 zha mm1xt 9haue of meiosis I butc,9z -*:dkh(c .n,v es msjger not meiosis II?
I. Crossing over occurs during prophase
II. Sister chromatids are pulled apart during anaphase
III. Chromosomes supercoil and become visible during prophase
A. I only
B. I and II only
C. I, II and III
D. II and III only
参考答案: A
本题详细解析:
Crossing over occurs between homologous pairs during prophase I, but not during prophase II, as homologous chromosomes have already been separated during meiosis 1. Choice A is correct. Statement II is incorrect as sister chromatids are pulled apart during anaphase II (Choices B, C and D). Statement III is incorrect, as chromosomes supercoil and become visible during prophase I and II (Choice D).
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