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]
When does the random oridg,hvuj4,d/ :r- q5exauh z) ;gpb yl9entation of ho c:34u;ucm0.nol) m riv v2kssi.el+gmologous 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.
| 
