2.3.5 Meiosis

Question 1

Prophase 1

Answer 1

Chromosomes condense and become visible. Homologous chromosomes link together to form chiasmata. Known as a bivalent
Crossing over takes place, the nuclear membrane breaks down and centrioles move to opposite poles of the cell

Question 2

Metaphase 1

Answer 2

The pairs of homologous chromosomes, are now lined at equator of the spindle apparatus

Question 3

Anaphase 1

Answer 3

The spindle fibres shorten, and homologous chromosomes move to opposite poles for this to happen the chiasmata between the homologous chromosomes break

Question 4

Telophase 1

Answer 4

Chromosomes are at opposite poles of the cell. At this point the nuclear membranes reform and chromosomes uncoil back to their chromatin state. The cell undergoes cytokinesis, dividing into two cells (these cells are haploid as they no longer contain pairs of homologous chromosomes).

Question 5

Prophase 2

Answer 5

The chromosomes condense and become visible again. Nuclear membrane breaks down and spindle fibres begin to develop

Question 6

Metaphase 2

Answer 6

The chromosomes are lined up on the equator of the spindle apparatus

Question 7

Anaphase 2

Answer 7

The centromere of each chromosome divides. Spindle fibres shorten. Chromatids are now pulled to opposite poles of the cell

Question 8

Telophase 2

Answer 8

The chromatids have reached the poles of the cell. We now call them chromosomes. The nuclear membranes reforms and chromosomes uncoil back to their chromatin state