Chapter 3 Review Sheet

Ecology

1. __________ is the scientific study of interactions among __________ and between organisms and their _____________.
2. The __________ contains the combined portions of the planet in which all of life exists, including _________, _________, and _________, or atmosphere.
3. To understand the various relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual of a particular species to a __________, ___________, ____________, __________, to the entire biosphere.
4. Scientists conduct modern ecological research according to three basic approaches: ____________, _____________, and ____________.
5. __________ is the main energy source for life on Earth. In a few ecosystems, some organisms rely on the energy stored in inorganic _________ __________.
6. The two processes by which organisms produce energy-rich carbohydrates are _______________ and _______________.
7. Energy flows through an ecosystem in _______ direction(s), from the sun or inorganic compounds to __________or producers and then to various __________ or __________.
8. In addition to herbivores, another type of consumer is a(an)

I. Carnivore

II. Omnivore

III. Detritivore

a) I only

b) II only

c) I and II only

d) II and III only

e) I, II, and III

9. The series of steps in which a large fish eats a small fish that has eaten algae is an example of a ___________. And when a number of these are put together to form a complex network of feeding relationships, then it is called a _____________.
10. Only about _____ percent of the energy available within one __________ level is transferred to organisms at the next level.
11. An ecological ____________________ is a diagram that shows the relative amounts of energy or matter contained within each trophic level of a food chain or food web.
12. A __________ pyramid shows the total amount of living tissue within each tropic level. A __________ pyramid shows the amount of individual organisms at each trophic level.
13. Unlike the flow of energy, __________ is recycled within and between ecosystems.
14. Which of the following is NOT true about matter in the biosphere?

a) Biogeochemical cycles transform and reuse molecules.

b) The total amount of matter decreases over time.

c) Water and nutrients pass between organisms and the environment.

15. The order of certain steps in the water cycle are:

a) Precipitation, condensation, transpiration, and runoff.

b) Evaporation, condensation, transpiration, and precipitation.

c) Evaporation, condensation, precipitation, and runoff.

d) Condensation, transpiration, precipitation, and evaporation.

16. Every living organism needs ____________ to grow and carry out essential life functions. Like water, these are passed between organisms and the environment through ___________________ cycles.
17. Human activity, such as the burning of fossil fuels is a process involved in the ___________ cycle.
18. In the nitrogen cycle, bacteria that live on the roots of plants

a) break down nitrogen compounds into nitrogen gas.

b) denitrify nitrogen compounds.

c) change nitrogen gas into plant proteins.

d) change nitrogen gas into ammonia.

19. Phosphorus is essential to living organisms because it forms part of important life-sustaining molecules such as _______ and _______. Most phosphorus exists in the form of inorganic phosphate. Some phosphate stays on land and cycles between __________ and the __________. It is also found in ___________ sediment.
20. One factor that controls the primary __________ of an ecosystem is the amount of available ____________, which if in short supply will cause the ecosystem’s growth to be ___________.