BIOLOGY 2 AP Ch. 33 Objectives

1. Describe the chemical composition of plants including:
1. Percent of wet weight as water.
2. Percent of dry weight as organic substances.
3. Percent of dry weight as inorganic minerals.
2. Explain how hydroponics culture is used to determine which minerals are essential nutrients.
3. Distinguish between macronutrient and micronutrient.
4. Recall the nine macronutrients required by plants and describe their importance in normal plant structure and metabolism.
5. List seven micronutrients required by plants and explain why plants need only minute quantities of these elements.
6. Explain how a nutrient’s role and mobility determine the symptoms of a mineral deficiency.
7. Explain how soil is formed.
8. Explain what determines the texture of topsoil and list the type of soil particles from coarsest to smallest.
9. Describe the composition of loams and explain why they are the most fertile soils.
10. Explain why plants cannot extract all of the water in soil.
11. Explain how the presence of clay in soil helps prevent the leaching of mineral cations.
12. Define cation exchange, explain why it is necessary for plant nutrition, and describe how plants can stimulate the process.
13. Explain why soil management is necessary in agriculture systems but not in natural ecosystems such as forests and grasslands.
14. List the three mineral elements that are most commonly deficient in farm soils.
15. Describe the environmental consequence of overusing commercial fertilizer.
16. Explain how soil pH determines the effectiveness of fertilizers and a plant’s ability to absorb specific mineral nutrients.
17. Describe problems resulting from farm irrigation in arid regions and list several current approaches to solving these problems.
18. Describe precautions that can reduce wind and water erosion.
19. Define nitrogen fixation and write the overall equation representing the conversion of gaseous nitrogen to ammonia.
20. Distinguish between nitrogen-fixing bacteria and nitrifying bacteria.
21. Recall the forms of nitrogen that plants can absorb and describe how they are used by plants.
22. Beginning with free-living rhizobial bacteria, describe the development of a root nodule.
23. Explain why the symbiosis between a legume and its nitrogen-fixing bacteria is considered to be mutualistic.
24. Recall two functions of leghomoglobin and explain why its synthesis is evidence for coevolution.
25. Describe the basis for crop rotation.
26. Describe agricultural research methods used to improve the quality and quantity of proteins in plant crops.
27. Describe modifications for nutrition that have evolved among plants including parasitic plants, carnivorous plants and mycorrhizae.