Chapter 10 Questions and Answers

Chapter 10

Pg. 243 1-5
1. The two reasons why cells divide is because the larger cell becomes the more demands the cell places on its DNA and the more trouble the cell has moving enough nutrients and wastes across the cell membrane.
2. A cell's DNA is like books in a library because a larger cell would have to make greater demands on its available genetic "library."
3. The solution caused by cell growth is understanding the relationship between a cell's colume and its surface area.
4. The cell's volume increases more rapidly as the cell increases in size.
5. Surface Area= 96cmsquared, Volume= 64cmcubed, Ratio= 1.5:1


Pg. 249 1-6
1. The main events of the cell cycle is that a cell grows, prepares for division, and divides to form two daughter cells.
2. The four phases of mitosis are Prophase: The chromatin condenses into chromosomes. The centrioles separate, and a spindle begins to form. The nuclear membrane breaks down. Metaphase: The chromosomes line up across the center of the cell. Each chromosome is connected to a spindle fiber at its centromere. Anaphase: The sister chromatids separate into indvidual chromosomes and are moved apart. Telophase: The chromosomes gather at opposite ends of the cell and lose their distinct shapes. Two new nuclear membranes form.
3. During interphase the cell grows and replicates its DNA and centrioles.
4. Chromosomes are made up of DNA which carries the cell's coded genetic information.
5. Prokaryotic cells divide by drawinf inward until the cytoplasm in pinched into two nearly equal parts which is the proccess in cytokinesis.
6. The simliarity is that they are both seperated into two new cells and the difference is how they are split the animal cell is split when the cytoplasm is pinched and the plant cell splits from a cell plate.

Pg. 252 1-5
1. The chemicals that regulate the cell cycle are cyclins which regulate the timing of the cell cycle in eukaryotic cells.
2. Cancer cells do not respond to the signals that regulate the growth of most cells. As a result, they from masses of cells called tumors that can damage the surrounding tissues.
3. Cells respond to contact with other cells by making their neighboring cells to slow down or stop their cell cycle.
4. Cancer can be considered a disease of the cell cycle becuase they have a defect in a genewhich normally halts the cell cycle until all chromosomes have been properly replicated.
5. If cyclin was injected into a cell that was in mitosis then would cause a mitotic spindle to form because it seemed to regulate the cell cycle.

Pg. 257 1-10
1. A
2. C
3. B
4. C
5. C
6. A
7. C
8. B
9. A
10. A