Mitosis and Meiosis Flashcards
What stage does meiosis first arrest at and where in the reproductive journey? In the oocyte.
It arrests at prophase I, this happens before birth
What stage does meiosis arrest at the second time and where in the reproductive journey? In oocyte.
Metaphase II, this happens following ovulation
What causes completion of meiosis II in the oocyte
fertilisation
When does meiosis begin in the testis
Begins at puberty and is completed in one go
How many cells are produced at the end of meiosis I and what is their genetic complement?
2 haploid non-identical cells
How many cells are produced at the end of meiosis II and what is their genetic complement
4 haploid non-identical cells
What causes genetical difference between daughter cells following meiosis?
Crossing over and independent assortment
What happens in prophase I
Thickening and matching up to homologous chromosomes and crossing over/ random assortment
What happens at metaphase I
The homoglous chromosomes line up along the middle of the cell
What happens at anaphase I
The chromosomes are pulled to opposite polls of the cell by spindle fibres
What happens at telophase I
Nucleus forms and cytokinesis occurs
What happens at Prophase II
Chromosomes thicken and condense
What happens at Metaphase II
The chromosomes line up single file along the equator
What happens at anaphase II
Spindle fibres pull chromatids to opposite poles of the cell
What happens at Telophase II
Nucleus forms and cytokinesis occurs producing 4 haploid non-identical gametes
