Take the 2-minute tour ×
Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. It's 100% free, no registration required.

This is from SAT subject biology test practice question. The answer it gave me was both chiasmata and centromeres. I can understand they are held by chiasmata but why also centromeres? I looked it up, I didn't find anywhere mentioned that they are held by centromeres also, only synaptonemal complex and chiasmata.

tetrads are truly held by spindle fibers on centromeres too, but isn't the question asking what hold them together? Even without spindle fibers, they can still be held by chiasmata I guess.

share|improve this question

1 Answer 1

A recombinase only active during meiosis - Dmc1 and a general recombinase Rad51 coat the single-stranded DNA to form nucleoprotein filaments. These filaments hold the homologs together at the chiasma, the point of attachment during crossing over.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.