meiosis Flashcards
1
Q
define ‘homologous’
A
chromosomes with the same genes but different alleles
2
Q
define ‘bivalent’
A
pair of chromosomes lined up at equator
3
Q
define ‘chromatid’
A
one of the 2 identical halves of a chromosomes AFTER replication
4
Q
define ‘haploid’
A
- contains 1 set of chromosomes from 1 member of the homologous pair
- 23
5
Q
define ‘diploid’
A
- contains 2 sets of chromosomes from both members of the homologous pair
- 46
6
Q
what is a reduction division?
A
- chromosomes number is 1/2 of parent cell (haploid)
- during meiosis 1
- the haploids fuse to form diploids
7
Q
how many chromosomes and chromatids at the start of interphase?
A
- 46 chromosomes
- 0 chromatids
8
Q
how many chromosomes and chromatids at the start of prophase 1?
A
- 46 chromosomes
- 92 chromatids
- replication has taken place so twice as many chromatids as chromosomes
9
Q
how many chromosomes and chromatids at the end of anaphase 1?
A
- 46 chromosomes
- 92 chromatids
- the chromosomes have been pulled apart but no division yet
10
Q
how many chromosomes and chromatids at the start of prophase 2?
A
- 23 chromosomes
- 46 chromatids
- division has occurred so 1/2d
11
Q
how many chromosomes and chromatids at the end of metaphase 2?
A
- 23 chromosomes
- 46 chromatids
12
Q
how many chromosomes and chromatids at the end of telophase 2?
A
- 23 chromosomes
- 0 chromatids
