Meiosis Flashcards
What is a zygote?
A fertilised egg.
What are the two rounds of meiosis division called?
Meiosis 1 and meiosis 2
What is chiasma?
When chromosomes exchange DNA in genetic crossing over
What causes variation in meiosis?
Independent assortment and crossing over
What happens during prophase 1?
Chromosomes come together, homologous pairs, chiasma could occur.
What happens during metaphase 1?
Chromosomes lie at equator randomly (independent assortment).
What happens in anaphase 1?
Chromosomes separate as spindle fibres shorten, each pole receives one from each homologous pair, random mixture of maternal/paternal.
What happens in telophase 1?
Chromosomes have reached the poles, start to dissolve, nucleus appears, cell goes into ‘rest phase’.
What happens during prophase 2?
New spindle fibres form, chromosomes reappear, nucleus disappears.
What happens in metaphase 2?
Line up on equator, independent assortment.
What happens in anaphase 2?
Chromatids move to poles, centromeres divide, spindle fibres shorten, pulling chromatids to opposite poles.
What happens in telophase 2?
Chromosomes reach the poles, dissolve, nucleus reappears, four cells made each with a haploid number of chromosomes.
What does meiosis create?
Haploid cells
