Biology 213 Practice Key 1. (4) Explain the difference between a macronutrient and a micronutrient and cite two examples of each category? Macronutrients are the minerals needed by the plant in greater concentrations to maintain its life. These are CHOPKNS plus Ca and Mg. Micronutrients are those minerals needed in minimal concentrations (<0.1% of dry weight). These are Fe, B, Cl, Mo, Cu, Mn, Ni, & Zn. 2. Macronutrients are primarily used to? for a plant. A. build structure B. regulate enzymes C. store energy D. both A and C 3. (4) Explain how Julius Sachs experiments showed the essential nature of plant nutrients? Julius Sachs would establish growing plants with their roots in a liquid environment and either add or subtract various minerals to check for their concentration requirements. This technique is called hydroponic culturing. 4. Which of the following describes the fate of most of the water taken up by a plant? A. solvent use. B. lost by transpiration. C. H + source for photosynthesis. D. force for turgidity 5. The bulk of the dry weight of a plant is derived from A. hydrogen from H 2 O. B. mineral uptake. C. carbon dioxide. D. oxygen from H 2 O. 6. (5) Explain the difference between mobile and immobile nutrients in terms of plants? Mobile nutrients are those that have not been incorporated into the plants permanent structures like Cl, Mg, N, P, K, and S and can still be transported through the phloem, whereas immobile are those that have been permanently (relatively) bound into the molecules of the plants structure like B, Ca, and Fe. 7. Which of the following nutrients is important in cytochrome function? A. chlorine B. iron C. copper D. molybdenum 8. Which of the following nutrients is important in lignin biosynthesis? A. chlorine B. iron C. copper D. molybdenum Biology& 213 1
9. (5) Name the three most common elements that lead to mineral deficiency in plants and name two symptoms seen as a result of mineral deficiency? Most mineral deficiencies involve N, P, and K and the symptoms involve leaf coloring or shriveling. These symptoms will involve younger tissue first due the mineral demands of growing tissue. 10. (4) Describe the forces that form soil. Soil is formed basically by the weatherization of rock be that by wind, water, or mechanical breakdown (lava flows, earthquakes, etc.). Added to this is the organic matter via by the decomposition of living organisms or their assorted lost parts. 11. The soil horizon that provides the best plant growth material because of it thickness is the A. O horizon. B. A horizon. C. E horizon. D. On the horizon. 12. The soil horizon where rocks are beginning to form is the A. O horizon. B. A horizon. C. E horizon. D. R horizon. 13. The soil order that best supports plant growth is the 14. The soil order that least supports plant growth is the 15. The soil that supports areas of vast gymnosperm forests is the 16. (4) Describe the texture of a soil that supports great plant growth? Soil that contains a balance of sand, silt, and clay with various sized pieces of each would provide the best growing soil for plants. Biology& 213 2
17. (4) Describe why the texture you described in question #16 is beneficial to plant growth? The texture is important to provide many available ionic binding sites for cations, places where water can collect, and sites for oxygen to be held. 18. (3) Explain why soil ph is so critical for successful plant growth? Plants use an H + proton pumping action (ATP driven) to move H + out into the soil so that other cations can be loosened from the soil particles and then available to be absorbed by electrical concentration gradients. If the ph were too acidic or basic for the plant this activity would require more energy and the plants health would be affected. 19. Which soil mineral is most likely leached away during a hard rain? A. Na + B. K + C. Ca ++ - D. NO 3 20. The conversion of NO 3 into N 2 is called A. nitrogen fixation. B. denitrification. C. nitrification. D. ammonification. 21. The conversion of N 2 into NH 4 is called A. nitrogen fixation. B. denitrification. C. nitrification. D. ammonification. 22. (4) Who really runs the nitrogen cycle and what is their role in the cycle? Soil nitrogen fixing bacteria and various fungal species are the critical organisms that assist in the operation of the nitrogen cycle by converting nitrates and nitrites into ammonium. 23. (3) Why is phytoremediation important in today s world? Phytoremediation is the process where we grow certain species of plants in areas with soil contamination (usually heavy metals) and the plants then can incorporate the contaminants into their bodies and remove them from the soil. Once concentrated in the plant body the plants are removed making it easier to remove the contaminant from the soil by removing the plant. Biology& 213 3
24. Based on studies of plant evolution, which flower part is not a modified leaf? A. stamen B. receptacle C. sepal D. carpel 25. In the life cycle of an angiosperm, which of the following stages is diploid? A. generative nucleus of a pollen grain B. megaspore C. polar nuclei of the embryo sac D. microsporocyte 26. (4) Describe the function of the synergid cells and the polar nuclei in the embryo sac? The synergid cells of the embryo sac function to attract and guide the pollen tube to the egg, while the polar nuclei will be fertilized by sperm and then develop into the endosperm. 27. (4) Discuss the reasoning behind the double fertilization that occurs in the embryo sac of angiosperms? Double fertilization involves the fertilization of the egg by a sperm for normal embryonic development and the fertilization of the polar nuclei to develop the endosperm or an internal food source for the embryo. 28. (4) Compare and contrast the function of the radicle and the hypocotyl in the germination of an angiosperm. The radical emerges from the seed to become the first roots and provide water and minerals to the developing tissues of the embryo, while the hypocotyl contains the cotyledons which protect the embryo through the soil and begin photosynthesis once above ground. Biology& 213 4
29. Which of the following plant parts are produced by asexual reproduction? A. leaves B. flowers C. stems D. all the above 30. Which of the following supports the development of the embryo? A. cotyledon B. endosperm C. radicle D. soil 31. (4) Explain the steps of a G-protein response to a first messenger? The binding of a first messenger (ligand like a hormone, amino acid, or ion) to a G- protein linked receptor cause the binding of a GTP to the G-protein. Once the GTP binds the g-protein migrates along the internal phospholipid heads until it reaches an adenylyl cyclase that releases a secondary messenger camp to cause (usually a protein kinase to become active) some intracellular response. 32. (12) Match the plant hormones in column A with the effects in column B. Some will have more than one answer. E G Auxin A. Inhibits growth and promotes stomata closer B. Promotes seed dormancy F H Cytokinins C. Promotes ripening of fruit D. Promotes xylem but inhibits phloem differentiation L J Gibberellins E. Promotes formation of lateral and adventitious roots F. Modifies apical dominance from the roots D K Brassinosteroids G. Regulates development of fruit H. Delays leaf senescence A B Abscisic Acid I. Promotes triple response in seedlings J. Promotes fruit growth C I Ethylene K. Promotes seed germination and pollen tube elongation L. Stimulates pollen development and pollen tube growth Biology& 213 5