Exam 18: Ecosystems

Your spacecraft crash-lands on an airless, lifeless moon. All that survives, along with the crew and you, are some chickens, cornflakes, and vitamins. The air and water recyclers are functioning. To maximize the food supply until a rescue craft arrives, you and the crew should

Almost all life on Earth is directly or indirectly dependent on

Match each term to its correct description below. -Found at the poles and on mountaintops, the vegetation of this biome is dominated by low-growing flowering plants, and the rock landscape is covered in mosses and lichens. Rodents provide food for carnivores like foxes and wolves. The few large mammals include bears and musk oxen.

Explain why ecosystems do not always have sharply defined physical boundaries.

Human activities

If there are 5,000,000 kcal of energy stored in grain that could be fed either to beef cattle or humans and you choose to feed the grain to the cattle to fatten them up for the humans, how many kcal would now be available as beef to feed the humans?

When humans consume rice they occupy which trophic level of a food chain?

If there are 5,000,000 kcal of energy stored in grain that could be fed either to chickens or humans and there is a small village of starving people that need to be fed, what is the most efficient way to feed the majority of the villagers?

Energy does not cycle through an ecosystem. This is because energy enters an ecosystem through photosynthesis as it changes to chemical energy. This is then used to fuel metablic activities

Why are deserts and tundra among the least productive terrestrial biomes?

What is the primary difference between consumers and decomposers?

If there are 50 kcal of energy in the tertiary consumer trophic level, how many kcal would you expect to find in the primary consumer level?

Producers capture energy from the ________ and transform it into fuel energy that passes up the food chain as one organism eats another.

How might a decline in phytoplankton affect the climate of Earth?

Match each term to its correct description below. -This biome is commonly found in both temperate and tropical latitudes. It does not receive enough moisture to support vigorous tree growth, so it is dominated by grasses and herbaceous plants. Burrowing rodents like voles and prairie dogs are common.

Rabbits, foxes, tapeworms, and fungi are all examples of

Which of the following statements about cycling within an ecosystem is FALSE?

Match each term to its correct description below. -Characterized by warm temperatures and roughly 12 hours of daylight all year, this biome receives either seasonally heavy rains or year-round rains that leach nutrients from the soil. Much of the soil nutrients are locked up in the biomass of the heavy vegetation. This biome is one of the most richly biodiverse and productive ecosystems on the planet.

The chemical and physical components of an ecosystem are considered to be ________ or nonliving.

Which of the following series best represents the energy flow in an ecosystem?