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

1. Energy flow                 

2. Decomposition

3. Productivity                 

4. Stratification

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 inverted in shape

3. It is upright in shape

4. Its base is broad

Of the total incident solar radiation the proportion of PAR is 

1. about 60%

2. less than 50%

3. more than 80%

4. about 70%

The biomass available for consumption by the herbivores and the decomposers is called

1. net primary productivity

2. secondary productivity

3. standing crop

4. gross primary productivity

Which one of the following is one of the characteristics of a biological community ?

1. Stratification 

2. Natality 

3. Mortality 

4. Sex-ratio

Which one of the following is not used for construction of ecological pyramids?

1. Dry weight

2. Number of individuals

3. Rate of energy flow

4. Fresh weight

Energy flow in an ecosystem is 

1. unidirectional

2. bidirectional

3. multi-directional

4. All the these 

Which of the following is/are incorrect:

A. All ecosystems are constant in size
B. In nature food chains exist, not food web
C. Flow of energy in ecosystem is unidirectional
D. Gene flow occurs between 2 different population (of 2 species)

1. A, C

2. A, D

3. A, B, D

4. A, B, C, D

The important step in the process of decomposition in order is:

Which of the following is false?

I. Quantity of biomass in a trophical level at a particular period is called standing crop.
II. The energy content in a trophic level is determined by considering a few individuals of a species         in that trophic level.
III. The succession that occurs in nearly cooled lava is called primary succession.
IV. Rate of succession is faster in the secondary succession
V. Phytoplankton are the pioneers in aquatic succession

1. Only II

2. Only III

3. Only V

4. Only I and IV