Multiple Choice QuestionsWhich of the following statement(s) regarding energy flow is/are false?
I. The detritus food chain begins with dead organic matter.
II. In aquatic ecosystem, detritus food chain is the major conduit for energy flow.
III. In terrestrial ecosystem a larger fraction of energy flows through grazing food chain.
IV. Producers belong to the first trophic level of the food chain.
II and III only
III and IV only
I and IV only
I and II only
I and II only
Match the following.
| Column I | Column II |
| A. Earthworm | 1. Catabolism |
| B. Bacterial and fungal enzymes | 2. Breaks down detritus into smaller particles |
| C. Accumulation of dark coloured amorphous substance | 3. Detritivores |
| D. Fragmentation | 4. Humus |
(A) - (3), (B) - (2), (C) - (4), (D) - (1)
(A) - (3), (B) - (l), (C) - (4), (D) - (2)
(A) - (2), (B) - (1), (C) - (4), (D) - (3),
(A) - (2), (B) - (3), (C) - (4), (D) - (1)
(A) - (2), (B) - (3), (C) - (4), (D) - (1)
The first trophic level in an ecosystem consists of
Primary producers
Primary consumers
Secondary producers
Secondary consumers
Secondary consumers
Select the correct statement
Phosphorus cycle is an example of gaseous nutrient cycle
The pyramid of biomass in sea is generally inverted
By the process of humification, soluble inorganic nutrients go down into the soil horizon
A given organism may not occupy more than one trophic level simultaneously
A given organism may not occupy more than one trophic level simultaneously
B.
The pyramid of biomass in sea is generally inverted
Phosphorus cycle is an example of sedimentary cycle. Pyramid of biomass of aquatic ecosystem is inverted. If decomposition leads to the formation of colloidal organic matter (humus), the process is called humification. Simple food chains are very rare in nature. This is because each organism may obtain food from more than one trophic level. Pyramid of energy is always upright because during the flow of energy from one trophic level to the next one. There always occurs a loss of energy.
The rate of biomass production and the rate of production of organic matter during photosynthesis are called respectively
Total productivity, primary production
Gross primary productivity, gross secondary productivity
Net primary productivity, secondary productivity
Net productivity, gross secondary productivity
Net productivity, gross secondary productivity
The gross primary productivity of an ecosystem is 170 tons organic matter and amount used in respiration is 50 tons. Calculate the net primary productivity of the ecosystem.
120 tons
100 tons
70 tons
12 tons
12 tons
The pioneer species in xerarch and hydrarch succession are respectively
Lichens and sedges
Phytoplanktons and sedges
Lichens and zooplanktons
Lichens and phytoplanktons
Lichens and phytoplanktons
Identify the ecologist from the given hints
(i) Has carried out long-term ecosystem experiments using outdoor plots
(ii) In his experiments he showed that increased diversity contributed to higher productivity
Ahmed Khan
David Tilman
Stanley Choen
Ernest Chain
Ernest Chain
Which of the following ecological pyramids is generally inverted?
Pyramid of energy
Pyramid of biomass in a forest
Pyramid of biomass in a sea
Pyramid of numbers in grassland
Switch
