Mitosis

Question 1

Interphase

Answer 1

• DNA unravelled + replicated (to double its genetic content) + organelles are also replicated + ATP content increased (provided energy for cell division)

Question 2

Prophase

Answer 2

• chromosomes condense - get shorter + fatter
• tiny bundles of protein (centrioles) start moving to opposite ends of the cell = forms a network of protein fibres (spindles)
• nuclear envelope breaks down + chromosomes lie free in the cytoplasm

Question 3

Metaphase

Answer 3

• chromosomes line up along middle of cell + become attached to the spindle by their centromere

Question 4

Anaphase

Answer 4

Centromeres divide separating each pair of sister chromotids
- spindles contract, pulling chromatids to opposite poles of the spindle (centromere first) - making chromotids appear v-shaped

Question 5

Telophase

Answer 5

• chromatids reach the opposite poles on the spindle
• they uncoil + become long and thin again - now called chromosomes
• nuclear envelope forms around each group of chromosomes = 2 nuclei form
• cytoplasm divides (cytokinesis) + there are now 2 new daughter cells genetically identical to original cell + each other
• mitosis finished + each daughter cell starts interphase again for next round of mitosis