Pg. 157

1. A
2. C
3. 6
4. C
5. D
6. B
7. B
8. D
9. D

10-2

1. During the cell cycle, a cell grows, prpares for cell division and divide to form 2 daughter cells. each of which then begins the cell cyle again.
2. Biologists divide the events of mitosis into 4 phases: prophase, metaphase, anaphase and telophase.
3. The cell grows and replicates its DNA and centrioles.
4. Chromosomes are made up of DNA.
5.Prokayrote cells divide during anaphase.
6.Cytokinesis takes place in an animal cell, the cell membrane is drawn inward until the cytoplasm is pinched into two nearly equal parts.

10-3

1. Cyclins regulate the timing of the cell cycle in eukarotic cells.
2. Cancer cells do not resond to the growth of most cells. As a result, they form masses of cells called tumors that can damage the surrounding tissue.
3.chromosome damage builds up when cells respond to contact with other cells.
4. Cancer cells don't respond to the signals that would normally stop them dividing. Masses of cancer cells form tumors that can damage normal tissue. These cancer cells are from a cancer tumor in the large intestine.
5. If cyclin were incerted into a cell that was in mitosis, the timing would be wrong.