Answers to homework due Tuesday, March 2, and Wednesday, March 3.

Textbook Page 219:1,3,4 (Due March 2)

1. Do all cells complete the cell cycle in the same amount of time?

No, the rate of completion varies widely depending on the cell and its function. (See diagrams at top of page 210)

3. How can disruption of the cell cycle result in cancer?

Uncontrolled cell division could cause tumor formation and cancer.

4. How does cancer affect normal cell functioning?

Cancer cells form masses of tissue that deprive normal cells of nutrients.

Textbook Page 224:1-10 (Due March 3)

1. What kind of environment is described when the concentration of dissolved substances is greater outside the cell than inside? b. hypertonic

2. Osmosis is defined how? b. as diffusion of water through a selectively permeable membrane.

3. An amoeba ingests large food particles by what process? c. endocytosis

4. Considering the surface area-to volume ration, what structure does surface area represent?

d. plasma membrane

5. Chromosomes are made of what? d. DNA

6. Which of the following does NOT occur during interphase? d. nuclear division

7. If a cell that has eight chromosomes goes through mitosis, how many chromosomes will the daughter cells have? b. 8

8. During metaphase the chromosomes move to the equator of what structure (shown in text)?

d. spindle

9. All but which of the following factors limit cell size? b. elasticity of the plasma membrane

10. Which of the following is NOT a known cause of cancer? d. bacterial infections