Metaphase in mitosis v meiosis I?

[sc4s2cg]

This question is taken from Kaplan 2015 Biology, Chapter 2, practice question 11.

Which of the following statements correctly identifies a key difference between mitosis and meiosis?

A. In metaphase of mitosis, replicated chromosomes line up in single file; in metaphase II of meiosis, replicated chromosomes line up on opposite sides of the metaphase plate.

D. During metaphase of mitosis, centromeres are present directly on the metaphase plate; during metaphase of meiosis I, there are no centromeres on the metaphase plate.

Could someone explain why A is wrong and D is correct?

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[basophilic]

i think this is just an interpretation thing.
in the second part of A, "line up on opposite sides of metaphase plate" probably means homologous chromosomes line up along metaphase plate so that each chromosome is not directly on the metaphase plate, but on opposite sides of it - this is false because single chromosomes line up ON metaphase plate in metaphase II of meiosis (alternatively, you could interpret the statement to mean the chromosomes are lining up perpendicularly to metaphase plate, which is also obviously false)
in part D, since mitosis involves chromosomes lining up single-file along the metaphase plate, their centromeres (region where chromatids intersect) will theoretically lie directly on the metaphase plate; in meiosis, because a pair of homologous chromosomes aligns on metaphase plate, the centromere of neither chromosome will lie on metaphase plate
try drawing it out

 

[sc4s2cg]

Hm. So you are interpreting A as saying that the chromosomes are lining up on the literal sides of the metaphase plate, instead of being in the plate itself? I can kind-of-sort-of see how D could be right.

 

[shefv]

in metaphase II of meiosis, replicated chromosomes line up on opposite sides of the metaphase plate.

This is talking about meiosis II - I was think that replicated chromosomes (i.e. tetrads) line up on the opposite sides of the metaphase plate in metaphase I. I crossed off A because mitosis and meiosis II are similar to each other.

 

[Kendjana]

I also picked A and could not understand why it was wrong. But I’m starting to understand a little.