Ecosystem

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels? [figure]

1. Level PC is "rats" and level SC is "cats"
2. Level PP is "phytoplankton" in sea and "whale" on top level TC
3. Level PP is "pipal trees" and the level SC is "sheep"
4. Level PC is "insects" and level SC is "small insectivorous birds"

Which one of the following is not a functional unit of an ecosystem?

1. Energy flow
2. Decomposition
3. Productivity
4. Stratification

The upright pyramid of numbers is absent in

1. Pond
2. Grassland
3. Lake
4. Forest

Which one of the following animals may occupy more than one trophic level in the same ecosystem at the same time?

1. Lion
2. Frog
3. Goat
4. Sparrow

Both, hydrarch and xerarch successions lead to:

1. Xeric conditions
2. Excessive wet conditions
3. Highly dry conditions
4. Medium water conditions

The breakdown of detritus into smaller particles by earthworm is a process called

1. Fragmentation
2. Catabolism
3. Mineralisation
4. Humification

Mass of living matter at a trophic level in an area at any time is called :

1. Humus
2. Detritus
3. Standing state
4. Standing crop

Of the total incident solar radiation the proportion of PAR is

1. About 60%
2. More than 80%
3. Less than 50%
4. About 70%

Which one of the following statements is correct for secondary succession?

1. It follows primary succession
2. It occurs on deforested site
3. It is similar to primary succession except that it has a relatively fast pace.
4. It begins on a bare rock.

Which one of the following statements for pyramid of energy is incorrect, whereas the remaining three are correct?

1. It shows energy content of different trophic level organisms
2. It is upright in shape
3. It is inverted in shape
4. Its base is broad