Name:………………………………………………………………..………………. Period:………………… Date Due:…………………………….. Refer back to this Units Guiding questions and answer them with as much evidence as possible: 1. What factors affect the size of populations within an ecosystem? 2. What are common threats to remaining natural ecosystems and biodiversity? How can these threats be reduced? Importance of Biodiversity 1. List three financial benefits of biodiversity. 2. Identify three ecosystem services of biodiversity. 3. Predict what would happen to other organisms in an ecosystem in which all the decomposers went extinct? 4. Think of a world in which there were only 5 types of animals and 5 types of plants. Would life be able to flourish in this environment? How would it be different from life today? 5. Many kinds of domestic crops are very different from their wild counterparts. How do you think this change happened? Genetically, how do you think domestic crops differ from the wild types? – Ecosystems 1. Define an ecosystem. 2. Distinguish between abiotic and biotic factors. Give examples of each. 3. Where does the energy come from for many ecosystems? 4. Name two nutrients that are recycled through an ecosystem. 5. How do land plants generate the energy they need for their metabolic energy? What do they do with excess energy? 6. Where do scavengers in an ecosystem obtain their energy from? How can scavenging be a beneficial strategy for an organism? 7. What is the role of decomposers? 8. What kind of problems can you foresee if every speck of carbon were turned into biomass? Why? Symbiosis 1. Define mutualism and commensalism. 2. Give examples of mutualism. 3. Explain why most parasites do not kill their host. Why is it in their own best interest to keep their host alive? 4. What are some symbiotic relationships humans share with other organisms? Competition & other Ecological Relationships 1. What is competition? 2. Describe the evolutionary effects of intraspecific and interspecific competition. 3. Why might organisms want to avoid interspecific competition? Name some examples of interspecific competition with negative effects on both members of the species. – 4. Is it possible for intraspecific competition to lead to the branching out of two species from one common ancestor? How might this occur? 5. Describe the relationship between a predator population and the population of its prey. 6. What is a keystone species? Give an example. 7. What is a limiting factor? 8. Some animals hunt in groups, but other animals hunt alone. What advantages or disadvantages might hunting alone offer to a predator? 9. Find an example of when human action affected one species in a predator-prey relationship and examine its effect on both species. Energy Flow & Trophic Levels in Ecosystems 1. Identify three different types of consumers. Name an example of each type. 2. What are photoautotrophs? Give an example of one. 3. What can you infer about an ecosystem that depends on chemoautotrophs for food? 4. What is the role of decomposers? 5. What do scavengers do? Give an example of a scavenger. 6. What is a trophic level? 7. What do energy pyramids depict? 8. Explain how energy limits the number of trophic levels in a food chain or web. 9. Draw a terrestrial food chain that includes four trophic levels. Identify the trophic level of each organism in the food chain. Populations Structures and Growth Patterns 1. What is population density? 2. What are the differences between population density and distribution? 3. A population of 820 insects lives in a 1.2-acre area. They gather nectar from a population of 560 flowering plants. The plants live in a 0.2-acre area. Which population has greater density, the insects or the plants? Why? 4. What can you infer about a species that has a random pattern of distribution over space? A uniform pattern? 5. How does the age-sex structure of a population influence growth? 6. Assume that a population pyramid has a very broad base. What does that tell you about the population it represents? 7. Compare and contrast Type I and Type III survivorship curves. 8. Define immigration and emigration. 9. What is migration? Give an example. 10. Write the formula for the population growth rate. Identify all the variables. 11. What is dispersal? State why dispersal of offspring away from their parents might be beneficial 12. Describe exponential population growth. 13. Describe logistic growth. 14. What are density-dependent factors? 15. What does the carrying capacity refer to? 16. What are K-selected and r-selected species? Cycles; water, nitrogen, & Carbon 1. What is a biogeochemical cycle? Name an example. 2. Identify and define two processes by which water naturally changes from a solid or liquid to a gas. 3. Define exchange pool and reservoir, and identify an example of each in the water cycle. 4. Assume you are a molecule of water. Describe one way you could go through the water cycle, starting as water vapor in the atmosphere. 5. Why can't plants use nitrogen gas directly? 6. What is nitrogen fixation? 7. Explain why bacteria are essential parts of the nitrogen cycle. 8. What is ammonification? 9. What is the role of the carbon cycle? 10. Why is cycling carbon important? 11. Describe a major method that carbon is cycled. 12. How have human activities increased atmospheric carbon dioxide levels? 13. What does it mean to say that photosynthesis and respiration are gas exchange processes? 14. How do scientists learn about carbon levels in the past?
