Answer Key Copyright by McDougal Littell, a division of Houghton Mifflin Company Chapter Test A Multiple Choice 1. c 2. d 3. a 4. d 5. d 6. b 7. d 8. b 9. b 10. c 11. a 12. c 13. b 14. a 15. d Short Answer 16. mitosis 17. D 18. They are shown as an X. 19. In part B of the diagram, DNA condenses into tightly coiled chromosomes. 20. Sample answer: In part B, the chromsomes are duplicated and consist of two sister chromatids. In part D, the sister chromatids have separated from each other. 21. Accept any one: muscle cell, neuron, red blood cell. 22. capable of developing into acompleteorganismor differentiating into any of its cells or tissues 23. fertilized egg cells 24. The most specialized cells are muscle cells, neurons, and red blood cells. They can give rise to other closely related, specialized cells. 25. Sample answer: Even though most cells carry all the same DNA, cells can differentiate among the genes and use only certain ones. Depending on which genes are activated, a cell can differentiate into a muscle cell, neuron, or red blood cell. Answer Key 1
CHAPTER 5 CELL GROWTH AND DIVISION Chapter Test A Multiple Choice Choose the letter of the best answer. (15 credits) 1. If a cell cannot move enough material through its membrane to survive, then the ratio of its surface area to volume is 5. During which of the following stages shown in Figure 5.1 does the cytoplasm of a cell divide? a. too large. b. just the right size. c. too small. d. growing too quickly. Cell Cycle gap 1 2. Before a cell can proceed to mitosis from the gap 2 stage of the cell cycle, it must mitosis a. double in size. b. complete a full cell cycle. c. undergo cytokinesis. d. pass a critical checkpoint. FIG. 5.1 gap 2 synthesis 3. During interphase a cell grows, duplicates organelles, and a. copies DNA. b. divides the nucleus. c. divides the cytoplasm. d. produces a new cell. 4. Why do the cells lining the stomach divide more quickly than those in the liver? a. They are much smaller cells. b. They have fewer chromosomes. c. They need much more surface area. d. They undergo more wear and tear. a. gap 1 b. synthesis c. gap 2 d. mitosis 6. Kinases and cyclins are internal factors that a. cause apoptosis. b. control the cell cycle. c. cause cancer cells to break away. d. prevent mitosis. 7. Proteins from outside a cell that stimulate it to divide are called a. oncogenes. b. stem cells. c. cyclins. d. growth factors. Assessment Book Chapter Test A 93
8. Which statement describes the chromosomeshowninfigure5.2? 12. Which statement about the process of binary fission is true? FIG. 5.2 a. It is made up of two histones. b. It is made up of two chromatids. c. It is made up of two centromeres. d. It is made up of two telomeres. a. It does not involve the division of cytoplasm. b. It does not require any duplication of DNA. c. It does not take place in multicellular organisms. d. It does not produce genetically identical offspring. 13. A plant s leaf consists of a. a group of organs. b. various types of tissue. c. organs that form a system. d. many identical cells. 9. In a single-celled organism, mitosis is used for a. development. b. reproduction. c. growth. d. epair. 10. Which of the following is true of malignant tumors? a. They do not require treatment. b. They are easily removed through surgery. c. They can cause tumors in other parts of the body. d. They contain cells that stay clustered together. 11. One difference between a cancer cell and a normal cell is that a. cancer cells divide uncontrollably. b. normal cells divide uncontrollably. c. cancer cells cannot make copies of DNA. d. normal cells cannot make copies of DNA. 14. Cells in a developing embryo differentiate based on a. their location in the embryo. b. symmetry in the first division. c. their particular DNA. d. secretions from the embryo. 15. Which organism is capable of reproduction through asexual mitosis? a. horse b. oak tree c. bacterium d. starfish 94 Chapter Test A Assessment Book
Short Answer Use the diagram below to answer items 16 20. (5 credits) A C B D FIG. 5.3 16. What is the name of the process shown in the diagram? (The letters are for identification, but do not indicate the order of the process.) 17. Write the letter of the stage in the cycle that occurs last. 18. How are sister chromatids represented in the diagram? 19. Describe the events that take place in part B in the diagram. 20. How are the chromosomes shown in part B different from the chromosomes shown in part D? Assessment Book Chapter Test A 95
Use the diagram below to answer items 21 25. (5 credits) inner cell mass fertilized egg muscle cells red blood cells FIG. 5.4 neurons 21. Name one type of cell shown in the diagram that is multipotent. 22. What does it mean for a cell to be totipotent? 23. Which of the cell masses shown in the diagram contains cells that are totipotent? 24. List the cells in the diagram that are the most specialized. What type of cell can these specialized cells give rise to? 25. Assume that all of the cells shown above are from the same organism and have the same genetic information. How do the cells differentiate into cells with different functions? 96 Chapter Test A Assessment Book