Stages of meiosis

Question 1

what happens in prophase 1?

6 points

Answer 1

chromosomes condense
nuclear envelope breaks down
spindle fibres form
centrosomes move to opposite poles
homologous chromosomes pair up forming bivalents
crossing over occurs

Question 2

what happens in metaphase 1?

3 points

Answer 2

chromosomes line up in the middle
spindle fibres attach to centromeres
independent assortment occurs

Question 3

what happens in anaphase 1?

1 point

Answer 3

spindle fibres shorten separating the homologous chromosomes to opposite poles.

Question 4

what happens in telophase 1 + cytokinesis?

4 points

Answer 4

homologous chromosomes reach poles + de-condense
nuclear envelopes form
spindle fibres break down
cytoplasm splits > 2 haploid daughter cells.

Question 5

state the similarities and differences of meiosis 1 and 2 stages

Answer 5

prophase 2: same
metaphase 2: same - both independent assortment and crossing over occurs
anaphase 2: sister chromatids are pulled apart not homologous chromosomes.
Telophase 2 + cytokinesis: same but produces 4 haploid daughter cells.

Question 6

define crossing over

Answer 6

the exchange of genetic material between non-sister chromatids of homologous chromosomes

Question 7

define independent assortment

Answer 7

The random alignment and separation of homologous chromosomes