Mitosis

Question 1

Prophase

Answer 1

• The chromosomes condense and are now visible under a microscope.
• Centrioles migrate to opposite poles of the cell, forming spindle fibres.

-The nucleolus disappears and the nuclear envelope starts to break down, leaving the chromosomes free in the cytoplasm.

Question 2

Metaphase

Answer 2

• The chromosomes line up at the equator of the cell.
• Each chromosome attaches to the spindle by their centromere.

Question 3

Anaphase

Answer 3

• The centromeres divide to separate each pair of sister chromatids.
• The spindle fibres contract and shorten to pull the chromatids to opposite poles of the cell.
• Each chromatid is pulled by its centromere, causing them to take on a ‘V’ shape when viewed under a microscope.

Question 4

Telophase

Answer 4

• The chromatids reach the opposite poles of the cell where they uncoil to become long and thin chromosomes again.
• A nuclear envelope forms around each set of chromosomes to form two nuclei and the nucleolus starts to reform.