The minimum requirement for an ecosystem to recycle nutrients present in it would be:
1. | producers |
2. | producers and decomposers |
3. | producers, primary consumers, and decomposers |
4. | producers, primary consumers, secondary consumers, and decomposers |
Net primary productivity is the gross primary productivity minus:
1. | that which is consumed by herbivores |
2. | that which is consumed by the producer in metabolism |
3. | secondary productivity |
4. | loss due to mortality |
Most organic material is converted to carbon dioxide, which can then be utilized in primary production by:
1. autotrophs
2. secondary consumers
3. herbivores
4. carnivores
The best way to describe an ecosystem would be that they are:
1. | processors of energy and transformers of matter. |
2. | processors of matter and transformers of energy. |
3. | processors of matter and energy. |
4. | transformers of matter but not of energy. |
The amount of carbon dioxide in the atmosphere is:
1. increasing
2. decreasing
3. holding steady
4. fluctuating wildly
The ecosystem that can survive in the absence of the Sun would be:
1. | tropical rainforest | 2. | tundra |
3. | benthic ocean | 4. | desert |
An important feature of the phosphorus cycle is that its reservoir is in:
1. aquifers
2. soil and rocks
3. the atmosphere
4. the sun
Most organic carbon on Earth is found in:
1. Atmosphere
2. Oceans
3. Biomass
4. Sedimentary rocks
The generation of biomass of heterotrophic (consumer) organisms in a system is termed:
1. | biogeochemical cycles | 2. | net primary productivity |
3. | gross primary productivity | 4. | secondary productivity |
In an open ocean, the pyramid of biomass is often inverted. How can this support higher trophic levels?
1. | The food produced by primary producers is of high quality |
2. | The primary producers grow and reproduce at high rates |
3. | Primary producers are very abundant. |
4. | The predators at higher trophic levels are very efficient |