Which of the following statement is incorrect?
1. | Any calculations of energy content, biomass or numbers, has to include all organisms at that trophic level. |
2. | The base of each pyramid represents the producers or the first trophic level while the apex represents tertiary or top level consumer. |
3. | The trophic level represents a functional level, not a species as such. |
4. | A given species occupies only one trophic level in the same ecosystem at the same time. |
The pyramid of biomass in the sea is generally
1. Upright
2. Inverted
3. Bell-shaped
4. Rectangular, stable.
Why does the pyramid of energy always upright?
1. Because energy cannot be destroyed.
2. Smaller organisms have more potential energy than larger ones
3. Because when energy flows from a particular trophic level to the next trophic level, some energy is always lost as heat at each step.
4. More than one statement is correct.
Which of the following is not a limitation of ecological pyramids?
1. It does not take into account the same species belonging to two or more trophic levels.
2. It assumes a simple food chain, something that almost never exists in nature;
3. It does not accommodate a food web.
4. Saprophytes are given a special place in ecological pyramids.
Which of the following group of organisms is not included in the ecological pyramids?
1. Herbivores
2. Carnivores
3. Saprophytes
4. Predators
In response to the changing environmental conditions, composition and structure of a community-
1. Remains constant
2. Constantly changes
3. Changes sometime
4. Never changes
What do you mean by ecological succession?
1. One community is succeeded by another
2. One community is dominant over another
3. The gradual and fairly predictable change in the species composition of a given area
4. Success of the ecological community.
During succession some species colonise an area, what does happen to the native species then?
1. Decline and even disappear
2. Flourish equally
3. Migrate
4. Decline in number
Ecological succession occurs-
1. In a species
2. In population
3. In a community
4. All of the above
Nature of change in community during succession is –
1. Orderly, sequential and parallel with the changes in the physical environment.
2. Independent of the changes in the physical environment.
3. Constant change
4. Depends upon the community