Assessment Chapter Test B Plant Responses In the space provided, write the letter of the description that best matches the term or phrase. 1. thigmonasty 2. auxin 3. ethylene 4. phytochrome 5. abscisic acid 6. cytokinin 7. nyctinasty 8. gibberellin 9. vernalization a. promotes cell division, promotes lateral buds b. closes stomata, promotes dormancy c. movement response to cycle of light and darkness d. promotes cell growth, inhibits lateral buds e. movement response to touch f. promotes growth by elongation and seed germination g. pigment involved in photoperiodism h. promotes fruit ripening and abscission i. growth response to touching a solid object j. low-temperature stimulation of flowering 10. thigmotropism In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 11. Indoleacetic acid, indolebutyric acid, and naphthalene acetic acid are examples of what group of plant hormones? a. auxins b. gibberellins c. abscisic acids d. cytokinins 12. The movement of sunflowers to face toward the sun is an example of a. gravitropism. b. chemotropism. c. heliotropism. d. thigmotropism. 13. Asters commonly flower in the summer. They would be categorized as a. day-neutral plants. c. short-day plants. b. long-day plants. d. long-night plants. 14. Which of the following is NOT a function of auxins? a. promoting apical dominance b. increasing fruit number c. promoting seed dormancy d. preventing fruit drop Modern Biology 243 Chapter Test
Plant Responses, Chapter Test B continued 15. In many plants, the branches near the shoot tip are shorter than branches near the base. This is referred to as a. chemotropism. c. thigmonasty. b. nyctinasty. d. apical dominance. 16. Which of the following is NOT a commercial use of auxins? a. the promotion of root formation on leaf and stem cuttings b. the prevention of fruit drop before maturity c. the increase in the number of fruits produced per plant d. the induction of stomatal closure 17. Cytokinins and auxins are used commercially to promote a. seed dormancy. b. root and shoot formation in tissue cultures. c. fruit ripening. d. fruit drop so that remaining fruits become larger. 18. Which of the following associations between a tropism and the environmental stimulus to which it responds is incorrect? a. chemotropism chemicals produced in a particular part of the plant b. gravitropism the force of gravity c. phototropism the duration of daylight d. thigmotropism contact with a solid object 19. Which of the following is NOT a function of nastic movements? a. discouraging insect feeding c. capturing insect prey b. reducing water loss d. growing toward a light source 20. Which of the following is the cause of the plant responses depicted in the illustration? a. auxin produced at the shoot tip b. gain and loss of turgor pressure in cells c. contact with an animal d. gravity DAY NIGHT Modern Biology 244 Chapter Test
Plant Responses, Chapter Test B continued 21. The critical night length for a plant is the number of hours of darkness required to a. induce flowering. c. convert P fr to P r. b. prevent flowering. d. convert P r to P fr. 22. Vernalization requires exposure to a. a critical night length to induce flowering. b. a critical night length to prevent flowering. c. cold temperatures to induce flowering. d. cold temperatures to prevent flowering. 23. Cell elongation on the shaded side of a plant is part of the phenomenon called a. gravitropism. c. thigmotropism. b. phototropism. d. chemotropism. Read each question, and write your answer in the space provided. 24. The expression one bad apple spoils the barrel refers to the effects of which type of plant hormone? Explain the meaning of the expression. 25. Why is leaf abscission an adaptive advantage? 26. What is the currently accepted explanation for the mechanism of gravitropism? 27. What is the fastest type of plant movement, and how fast does it occur? 28. Under what conditions, natural or artificial, will a long-day plant flower? 29. When do most biennial plants flower? Modern Biology 245 Chapter Test
Plant Responses, Chapter Test B continued Follow the directions given below. 30. The illustrations below depict experiments conducted by Fritz Went in the 1920s to determine the mechanism of phototropism. Refer to the illustrations as you answer questions a e. A Shoot tip excised Tip placed on agar block Chemicals in tip diffuse into agar block Agar block placed on another shoot with its tip removed Shoot grows in direction opposite location of agar block B Shoot tip excised Agar block without shoot tip Agar block placed on another shoot with its tip removed Shoot continues to grow straight upwards a. Based on your study of plant hormones, what kind of plant hormone is likely to have caused the shoot tip in part A of the experiment to bend as it grew? b. Which step, A or B above, served as a control in this experiment? Explain your answer. c. How could you test whether your answer to item a is correct? Modern Biology 246 Chapter Test
TEACHER RESOURCE PAGE ovule and fuse with the egg cell and the polar nuclei there. 27. Making cuttings involves growing new plants from pieces of stem, root, or leaf. Layering involves inducing root formation on a stem. Grafting involves attaching two or more plant parts to form a single plant. Tissue culture involves growing new plants from small pieces of tissue in sterile nutrient media. 28. Factors required to break dormancy in certain seeds include light, low temperature, and abrasion by acid or other agents. These help prevent seeds from germinating before environmental conditions are suitable for growth of the plant. 29. water, oxygen, and the appropriate temperature range 30. (a) 1. spores; 2. sperm; 3. eggs; 4. zygote (b) B and C (c) A (d) D (e) spores, male gametophyte, female gametophyte, sperm, and eggs Plant Responses Chapter Test A (General) 1. c 10. a 2. c 11. g 3. a 12. a 4. a 13. f 5. c 14. h 6. b 15. d 7. d 16. c 8. d 17. e 9. b 18. b 19. The result of the auxin spray on fruit trees depends on the plant s stage of development when the spray is applied. If auxin is sprayed on young fruits, some will drop off allowing the remaining fruits to grow larger. If it is sprayed on fruits several weeks before they are ready to be picked, it will prevent the fruits from dropping. 20. Roots grow downward under the influence of gravity. This is an example of gravitropism. Roots are positively gravitropic, because auxins accumulate along the lower side of the roots and the roots grow downward. 21. Heliotropism or solar tracking is the movement of leaves or flowers as they follow the sun s movements across the sky. 22. Plants are categorized as either shortday plants, long-day plants, or dayneutral plants. Short-day plants flower in the spring or fall when days are short and nights are long. Long-day plants flower in the summer when days are long and nights are short. Day-neutral plants are not affected by day length. 23. Cytokinins promote cell division and promote lateral bud development in dicots. 24. Nastic movements are plant movements that occur in response to environmental stimuli, but are independent of the stimuli direction. Examples include the Venus flytrap that closes when touched and the prayer plant that has leaves that fold up at night. 25. The changing leaf colors are a photoperiodic response and a temperature response to the short day, longer nights, and cooler temperatures of autumn. The leaves stop producing the green pigment chlorophyll, allowing the red, orange, and yellow pigments in the leaves to become visible. Plant Responses Chapter Test B (Advanced) 1. e 13. b 2. d 14. c 3. h 15. d 4. g 16. d 5. b 17. b 6. a 18. c 7. c 19. d 8. f 20. b 9. j 21. a 10. i 22. c 11. a 23. b 12. c 24. Ethylene; one rotting apple will produce ethylene gas, which stimulates nearby apples to ripen and spoil. 25. Leaf abscission causes dead, damaged, or infected leaves to drop to the ground rather than shading healthy leaves or spreading disease. Modern Biology 432 Answer Key
TEACHER RESOURCE PAGE 26. Auxins accumulate on the lower sides of horizontally oriented stems and roots. Auxins stimulate stem cells to elongate, resulting in upward growth of the shoot, and inhibit elongation of root cells, resulting in downward growth of the root. 27. Thigmonastic movements; some thigmonastic movements occur within a few seconds of a stimulus. 28. Long-day plants will flower when the number of hours of continuous darkness is shorter than critical night length, or when a period of darkness longer than critical night length is divided into two dark periods each shorter than critical night length. 29. Biennial plants flower in the spring of their second year of growth. 30. (a) auxin (b) step B; the agar block did not contain plant hormones, and no changes in growth were observed. (c) Synthetic auxin could be applied to an agar block and then the agar block placed on one side of a decapitated shoot tip. If the shoot tip were to bend in the direction opposite the location of the agar block, then the results would indicate that auxin causes the results observed in part A of Went s experiments. Introduction to Animals Chapter Test A (General) 1. a 12. a 2. d 13. e 3. d 14. g 4. a 15. a 5. d 16. f 6. b 17. h 7. c 18. c 8. c 19. i 9. a 20. d 10. b 21. b 11. b 22. mesoderm 23. radial symmetry 24. hermaphrodite 25. organogenesis Introduction to Animals Chapter Test B (Advanced) 1. f 13. g 2. h 14. d 3. m 15. b 4. e 16. b 5. k 17. a 6. j 18. d 7. a 19. c 8. b 20. b 9. l 21. c 10. i 22. b 11. d 23. d 12. c 24. Scientists have inferred that multicellular invertebrates may have developed from colonies of loosely connected flagellated protists. Colonial protists may have lost their flagella over the course of evolution as individualized cells in the colony grew more specialized. 25. Sponges have no body symmetry and no true tissues. 26. Segmentation refers to a body composed of a series of repeating similar units. It is not found in all animals; some invertebrate phyla are not segmented. 27. The coelom forms from rapid cell division in the blastocoel. The newly differentiated mesodermal cells spread out and completely line the newly formed coelom. 28. a. blastocoel; b. archenteron; c. coelom; d. schizocoely; e. blastocoel; f. coelom; g. archenteron; h. enterocoely 29. A human embryo undergoes radial, indeterminate cleavage; the coelom forms by enterocoely; and the blastopore becomes the anus. In contrast, a clam embryo undergoes spiral, determinate cleavage; the coelom forms by schizocoely; and the blastopore becomes the mouth. 30. a. invertebrates; b. both; c. invertebrates; d. both; e. both; f. invertebrates; g. vertebrates; h. both; i. vertebrates; j. both; k. both; l. invertebrates; m. both; n. both; o. vertebrates Modern Biology 433 Answer Key