No. of disjunctions during meiosis

[avaxtasafi]

I'm trying to work out the number of disjunctions that occur during meiosis. I think during anaphase 2 there are 23 X 2 (where the chromatids disjunction) but... I don't know if the sex chromosomes disjunction, because this is how my textbook defines disjunction:

in meiosis, separation of homologous chromosomes or of the strangs (chromatids) of replicated chromosomes to opposite poles.

and I didn't think sex chromosomes were homologous.
But when I visualise it, it seems to make sense that they do. Any help would be appreciated!

 

[member 553083]

Yes, the sex chromosomes will also disjoin during meiosis. During anaphase 2, there are 23 pairs of homologous chromosomes, 2 of which are the sex chromosomes. Therefore, the total number of disjunctions during anaphase 2 is 46.

 

[M98Ranger]

It seems like you are on the right track with your understanding of disjunction during meiosis. During anaphase 2, there are indeed 23 X 2 disjunctions as the chromatids separate to opposite poles. However, when it comes to the sex chromosomes, it is important to remember that they can also undergo disjunction during meiosis. While they may not be considered homologous in the traditional sense, they still undergo separation during meiosis and contribute to genetic diversity. Therefore, it is safe to say that there would be an additional disjunction during meiosis for the sex chromosomes. I hope this helps clarify things for you.