Holiday Assignment Hints
(updated for final time 12/27/05 11:15 PM)
19-1
  • Short Answer 2: ozone layer
  • 4. Critical Thinking: Think about a substance plants use to do photosynthesis that would harm the Earth's atmosphere if it was not removed. What is the general term for the change that could take place? What changes will this cause on the Earth?
  • Structures and Functions: Label each diagram as ecosystem, population, community, biosphere, organism. THEN label the diagrams 1 through 5, 1 being most inclusive.
19-2
  • Be sure you understand biotic and abiotic factors thoroughly! Precipitation may influence N2 availability, O2 solubility depends on water temperature
  • Regulators use energy to keep their body temperature within an optimal range even when the envoronmental conditions change. Conformers internal conditions change as the environment changes.
  • Generalists can eat a wider variety of foods and live in a wider variety of environments than can specialists.
20-2
  • Birth rate = growth rate - death rate
  • Short Answer 1:
    • birth rate = live births / population
    • death rate = death / population
    • growth rate = birth rate - death rate
  • Structures and Functions:
    • When describing the regions on the logistical model graph, tell whether birth rate and death rate are increasing or decreasing.
21-1
  • Critical Thinking, Short Answer 5, should be written as hypothesis and needs to include a reason.
21-2
  • Species richness, or the number of species in a community, is greater in the tropics (lower latitudes) because tropical habitats contain more energy to support more organisms.
  • Species richness is greater in habitats with larger area.
  • These communities are more stable because thre are more links between species.
22-1
  • Biomass is the organic material in an ecosystem.
  • A food chain is a single pathway of feeding relationships among organisms in an ecosystem. A food web is a series of interlinked food chains.
  • Energy transfer from lowest to highest trophic levels is not 100% because
    • some organisms die without being eaten
    • some biomolecules store energy that consumers cannot break down
    • some energy at lower levels is used up in cellular respiration and is not transferred
    • some energy is lost as heat
  • Decomposers are needed to free up nutrients in waste products and bodies of other organisms so that these nutrients can be recycled
22-2
  • The water cycle, the carbon cycle, and the nitrogen cycle are biogeochemical cycles that involve the movement of water, carbon, and nitrogen between the living and nonliving parts of an ecosystem.
  • Structures and Functions: what two processes are part of the water cycle? The carbon cycle? The nitrogen cycle?
  • The use of chlorofluorocarbons causes a decreased level of ozone in the upper atmosphere, which allows increased levels of UV radiation to reach the Earth's surface. This can cause harmful mutations in plant and animals, and increased levels of skin cancer in humans.
  • Burning fossil fuels causes increased levels of atmospheric CO2 which is thought to increase average global temperatures. This can cause changes in rainfall patterns and soil moisture, a higher sea level, shifting of agricultural regions, and disruption of natural ecosystems.
23-1
23-2
  • Species evenness considers how many individuals belong to each species in a community. If there are approximately equal numbers of individuals in each species present, the community is said to have high species evenness.
23-3
  • Conservation biology is a discipline that seeks to identify and maintain natural areas.
  • Restoration biologists seek to reverse major human-caused environmental changes and replace missing ecosystem components.
There will be opportunity for questions when you get to class on Tuesday. Be prepared to ask! I will be back, assuming no weather or flight issues.
e-mail me with questions
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