Homologous chromosomes?

Practice Question Solving
1

Cell division & sex determination

Which of the following statements is correct in both mitosis and meiosis?

  1. Parent cell has 46 chromosomes.

  2. Homologous chromosomes align adjacently on the midline.

  3. Sister chromatids separate.

A 1 only

B 2 only

C 1 and 2 only

D 1 and 3 only

E 2 and 3 only

The answer is A , can someone explain why it cant be D

2

Hey, where is this question taken from? In my opinion D is correct too.

2 Likes
3

Maybe because in meiosis 1 the sister chromatids aren’t separated? However yea D should be the answer unless the question was talking about mitosis and meiosis 1

3 Likes
4

Hi, this question is from BMAT ninja, and sorry i mixed up, the answer they’ve given is D .
I was a bit confused about the 2nd statement and thought the answer was E

2 Likes
5

yep! that’s the answer. Thanks !

6

Hi!
I think the answer can’t be A!
First sentence can be correct in mitosis and meiosis 1 , but because in meiosis II there are 23 chromosomes at the begining you can also consider the first statement as a wrong scentence.

In the second statement only in meiosis I the homologous pairs locate in the equater of the cell. So the second scentence is definitely wrong.

In the third sentence , sister chromatides are separated during mitosis and meiosisII. So this can be correct.

But pay attention to the question. It is saying that “in both meiosis and mitosis” it is not necessarily mentioned in which meiosis. So you should consider the entire meiosis, not specially just meiosis II or 1.
So I think the answer must be D.

7

so if homologous chromosomes along the equator do aline during meiosis 1, it still means that it occurs during meiosis since it isnt specified which stage of meiosis it should occur in?

8

It is asking an event which occures during both meiosis and Mitosis!
We can say that the homologous pairs align in the middle of the cell in the meiosis according to this question’s strategy. But in mitosis this doesn’t happen! Therefore, this statement is wrong.

9

oh yeah but homologous chromosomes do align but end to end during mitosis, I misunderstood what it meant by adjacently… now it’s more clear

1 Like