Animals take phosphorous from
(1) water
(2) plants
(3) rock
(4) soil.
Most animals that live in deep oceanic waters are
(1) Tertiary consumers
(2) Detritivores
(3) Primary consumers
(4) Secondary consumers
Keystone species deserve protection because these
(1) are capable of surviving in harsh environmental conditions
(2) indicate presence of certain minerals in the soil
(3) have become rare due to overexploitation
(4) play an important role in supporting other species.
Energy flow in an ecosystem is
(1) unidirectional
(2) bidirectional
(3) multi-directional
(4) All the these
In a stable ecosystem, which of the following limits the number of trophic levels?
(1) Biomass
(2) The number of nutrients
(3) Availability of nutrients
(4) Presence of contaminants that increase in concentration along the food chain
Most of the world's carbon is found:
1. As carbon dioxide in the atmosphere.
2. In living organisms.
3. As bicarbonate and carbonate ions dissolved in the oceans.
4. As carbonate minerals in sedimentary rock.
Photosynthesis and respiration are central to which cycle?
1. The nitrogen cycle
2. The carbon cycle
3. The phosphorus cycle
4. The sulfur cycle
Which of the following changes would not result in an increase in net primary production?
(1) Increased precipitation in an and area
(2) Increased soil fertility
(3) Increased latitude (moving from the equator toward the poles)
(4) Moving down a mountain to warmer temperatures
Grasslands can support greater grazing rates by herbivores than forests because:
(1) Grasslands receive more sunlight
(2) The net production of grasslands is greater
(3) Grasslands produce less woody plant tissue
(4) More of the grassland production is above ground
The amount of energy reaching an upper trophic level is determined by:
1. Net primary production
2. Net primary production and the efficiencies with which food energy is converted to biomass
3. Gross primary production
4. Gross primary production and the efficiencies with which food energy is converted to biomass