If 20 J of energy is trapped at the producer level, then how much energy will be available to peacocks as food in the following chain?
Plant → mice → snake → peacock
1. | 0.02 J | 2. | 0.002 J |
3. | 0.2 J | 4. | 0.0002 J |
Pheretima and its close relatives derive nourishment from:
1. Sugarcane roots
2. Decaying fallen leaves and soil organic matter
3. Soil insects
4. Small pieces of fresh fallen leaves of maize
In an ecosystem, the rate of production of organic matter during photosynthesis is termed as:
1. net primary productivity
2. gross primary productivity
3. secondary productivity
4. net productivity
What type of ecological pyramid would be obtained with the following data?
Secondary consumer: 120 g
Primary consumer: 60 g
Primary producer: 10 g
1. Inverted pyramid of biomass
2. Pyramid of energy
3. Upright pyramid of numbers
4. Upright pyramid of biomass
Detritus is
1. Dead raw material for decomposition.
2. Partially decomposed organic matter.
3. Dead remains of animals & plants.
4. Both 1 and 3
Read the statements given below and choose the correct option
Statement I : Decomposition is purely an anaerobic process.
Statement II : The rate of decomposition is controlled by chemical composition of detritus and climatic factors.
1. Only statement I is correct.
2. Only statement I is incorrect.
3. Both statements I and II are correct.
4. Both statements I and II are incorrect.
Consider the following four statements (A–D), select the correct option stating which ones are true (T) and which ones are false (F)
(A) | Organism at each trophic level depends on those at higher trophic levels for their energy demands. |
(B) | Each trophic level has a certain mass of living material at a particular time called standing crop. |
(C) | The amount of inorganic matter present in an ecosystem at a given time called standing state. |
(D) | The number of trophic levels in a grazing food chain is not restricted |
A | B | C | D | |
1. | T | T | F | F |
2. | F | T | F | T |
3. | T | F | T | F |
4. | F | T | T | F |
Mark the odd one with respect to shape of ecological pyramids.
1. Pyramid of energy.
2. Pyramid of number in grassland ecosystem.
3. Pyramid of biomass in aquatic ecosystem.
4. Pyramid of biomass in terrestrial ecosystem.
How many statements are correct about
decomposition?
(A) Oxygen independent process.
(B) Faster if detritus is rich in lignin and chitin.
(C) Light is the most important climatic factor for decomposition.
(D) Warm and moist environment favour decomposition.
1. One
2. Two
3. Three
4. Four
The secondary productivity means
1. Rate of increase in the biomass of autotrophs.
2. Rate of increase in the biomass of heterotrophs.
3. The rate at which the organic molecules are used up by an autotroph.
4. The rate at which inorganic molecules are used up by an autotroph.