9.2 Meiosis and Genetic Mutation Flashcards
1
Q
How many divisions are in meiosis and what are they called?
A
- 2
- Meiosis division 1
- Meiosis division 2
2
Q
What happens in early prophase I ? - 3 points
A
- chromosomes condense and become visible
- the nucleus membrane begins to disintergrate
- centrioles, double stranded chromosomes
3
Q
What happens in late prophase I ? - 3 points
A
- homologous chromosomes pair up and each pair is called a bivalent
- crossing over/recombination
- nuclear membrane is completely gone and centrioles are at opposite poles
4
Q
What happens in metphase I ? - 3 points
A
- bivalents line up along the centre of the cell
- independent assortment of chromosomes
- centrioles have moved to opposite ends and spindle fibres begin to form
5
Q
What happens in anaphase I ? - 2 points
A
- chromosomes DO NOT divide
- whole chromosomes are pulled by their centromeres by spindle fibres
6
Q
What happens in telophase I ? - 3 points
A
- the nuclear membrane reforms
- cytokenesis has occured
- daughter cells are now haploid
7
Q
What happens in prophase II ? - 1 point
A
- chromosomes condense
8
Q
What happens in metaphase II ? - 2 points
A
- chromosomes line up single file in the centre of the cell
- centrioles are at opposite, spindle fibres are formed
9
Q
What happens in anaphase II ? - 2 points
A
- spindle fibres pull chromatids to opposite ends
- centromere divides
10
Q
What happens in telophase II ? - 2 points
A
- cytokenesis produces 4 haploid daughter cells
11
Q
What stages occur in meiosis division 1? - 5 points
A
- early prophase I
- late prophase I
- metaphase I
- anaphase I
- telophase I
12
Q
What stages happen in meiosis division 2 ? - 4 points
A
- propahse II
- metaphase II
- anaphase II
- telophase II
13
Q
What does meiosis produce?
A
4
unique/different
haploid daughter cells
14
Q
Why is each daughter cell produced by meiosis unique and different? - 2 points
A
- crossing over
- random assortment
15
Q
When does crossing over happen?
A
Late prophase I
