1. During what stage of the cell cycle does the DNA replicate ?
Answer
Interphase stage.
2. One of the noticeable changes at the start of mitosis is that the chromosomes become visible. Describe what happens to chromosomes in order for them to become visible.
Answer
They need to condense by wrapping tightly around histones.
3. How do prokaryotes divide ?
Answer
Binary fission.
4. Complete the table according to the specific stage that cell is in.
Answer
5. Lengths of cell cycles differ depending on the type of cell. If the cell cycle takes 20 hours, calculate how long it takes to complete mitosis if the mitotic index is 20%.
Answer
20 × 0.2 = 4 hours
6. The table below shows two different cells during their cell cycle. One way that cancerous cells can be identified is by looking at how long they spend in specific parts of cell cycle. Identify which cells are cancer cells, A or B.
Answer
Cell B, because it spends a much shorter period of time in interphase, indicating uncontrolled cell division.
7. Place the stages of mitosis shown below in the correct order.
Answer
The order is C, D, A, B.
8. Describe what is occurring in stage D. Explain the importance of this stage.
Answer
All chromosomes line up at the equator so that sister chromatids can be separated. Spindle fibres attach to the centromeres to ensure this separation, allowing both cells to be genetically identical at the end of cell division.
9. Name the process that occurs after stage B.
Answer
Cytokinesis, or the division of the cytoplasm.
10. Complete the table below.
Answer
