Cell cycle

1. (b) chromatin replicates to form 2 sister chromatids

2. No u

3. (d) spindle fibres form

4. Interphase (Resting stage)

5. Cytokinesis (Division of cytoplasm)

6. (b) spindle fibres shorten and pull sister chromatids apart to opposite poles, forming daughter chromosomes

7. (b) furrow deepens to produce 2 genetically identical daughter cells

8. (b) centromere of chromosome attached to both sides of spindle fibre

9. (a) chromatin threads coil, condense and shorten to become chromosomes

10. (c) in plant cells, cell plate is formed by fusing vesicles between 2 nuclei dividing the cell into two. (no centrioles in plant cell)

11. 3. Anaphase

12. (a) in animal cells, furrows/ cleavage appear in cytoplasm between 2 nuclei

13. Mitosis (Nuclear division)

13.1. 1. Prophase

13.1.1. (c) daughter chormosomes uncoil and lengthen to become thin chromatin threads

13.1.2. (b) in animal cells, aster form around centrioles

13.2. (c) nucleolus and nuclear envelope disappear

13.3. 2. Metaphase

13.3.1. (a) chromosome line up at equator

13.4. (a) centromere divides

13.5. 4. Telophase

13.5.1. (a) spindle fibres break down

13.5.2. (b) nucleolus and nuclear envelope forms at each pole