Answer Key Copyright by McDougal Littell, a division of Houghton Mifflin Company Chapter Test A Multiple Choice 1. c 2. b 3. d 4. a 5. c 6. b 7. c 8. c 9. d 10. a 11. b 12. a 13. d 14. b 15. c Short Answer 16. two cells containing various organelles 17. Accept any two of the following: ER, ribosomes, mitochondria, central vacuole, chloroplast, nucleus, Golgi apparatus, vesicles, and lysosomes. 18. B 19. Plant cell 20. Cytoplasm. The cytoplasm fills up the space between the nucleus and the cell membrane. Cytoplasm is made up mostly of water. The water in the cytoplasm is necessary for maintaining the shape of the cell. 21. the cell membrane 22. phospholipids 23. The molecules are arranged in a double layer. The heads of the molecules form the outer surfaces of the membrane, and the tails form the inner part of the membrane. 24. Accept any of the following: These molecules strengthen the cell membrane; help materials cross the membrane; detect signal molecules and perform an action in response. 25. Accept any of the following: a higher concentration of a substance on the outside of the membrane than on the inside; a high concentration of molecules small enough to go through the membrane; a concentration gradient that goes down on the inside of the cell Answer Key 1
CHAPTER 3 Multiple Choice CELL STRUCTURE AND FUNCTION Chapter Test A Choose the letter of the best answer. (15 credits) 1. Which of the following is a major principle upon which cell theory is based? a. All cells form by free-cell formation. b. All cells have DNA. c. All organisms are made of cells. d. All cells are eukaryotic. 2. Identify the type of cell shown in Figure 3.1. 5. Which organelles supply energy to the cell? b. centrosomes c. mitochondria d. vacuoles 6. Which organelles contain enzymes that break down old cell parts? a. centrosomes b. lysosomes c. vacuoles d. chloroplasts 7. Which organelles are unique to plant cells? b. vacuoles c. chloroplasts d. centrosomes 8. Which process occurs inside the chloroplasts? FIG. 3.1 a. prokaryotic b. eukaryotic c. bacterial d. animal 3. Which organelle is the storehouse for most of a cell s genetic information? a. mitochondrion b. chloroplast c. centriole d. nucleus 4. Which phrase best describes rough ER? a. studded with ribosomes b. protected by vesicles c. connected to the Golgi apparatus d. stored in the central vacuole a. detoxification b. ribosome assembly c. photosynthesis d. protein synthesis Assessment Book Chapter Test A 53
9. Which type of receptor is shown in the diagram in Figure 3.2? outside ligand FIG. 3.2 inside receptor 13. Which process requires no energy from the cell? a. exocytosis b. endocytosis c. active transport d. facilitated diffusion 14. Which organelles are involved in the process called endocytosis? b. vesicles c. centrioles d. chloroplasts a. cytoplasmic b. membrane c. extracellular d. intracellular 10. A protein that detects a signal molecule and performs an action in response is called a a. receptor. b. ligand. c. vesicle. d. proton. 11. A solution that is hypotonic to a cell has a. more solutes than the cell. b. fewer solutes than the cell. c. the same concentration of solutes as the cell. d. toomanysolutes. 12. Transport proteins play a role in both a. passive and active transport. b. exocytosis and endocytosis. c. diffusion and vesicle transport. d. phagocytosis and passive transport. 15. Whichprocessisoccurringwhena vesicle fuses with the cell membrane and releases its contents outside the cell? a. endocytosis b. phagocytosis c. exocytosis d. osmosis 54 Chapter Test A Assessment Book
Short Answer Use the diagram below to answer items 16 20. (5 credits) A B C D E F G FIG. 3.3 16. Describe what is shown in Figure 3.3. 17. List two organelles shown in the diagram. 18. Which labeled structure is the site of photosynthesis? 19. Name the type of cell shown on the right side of the diagram. 20. Identify part A and explain how it contributes to the structure and shape of the cell. Assessment Book Chapter Test A 55
Use the diagram below to answer items 21 25. (5 credits) A FIG. 3.4 B 21. Whatisshowninthediagram? 22. What is the term for the molecules located in part A of the diagram? 23. Describe the arrangement of the molecules located in part A of the diagram. 24. What is one function of the molecules (B) that are embedded in the layers of part A? 25. What conditions would cause a molecule to diffuse from the outside of the structure showntotheinside? 56 Chapter Test A Assessment Book