Secondary succession takes place on/in:
The mass of living material at a tropic level at a particular time is called:
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
Match the following and select the correct option:
Column I | Column II | ||
(a) | Earthworm | (i) | Pioneer species |
(b) | Succession | (ii) | Detrivore |
(c) | Ecosystem service | (iii) | Natality |
(d) | Population growth | (iv) | Pollination |
1. A-(i), B-(ii), C-(iii), D-(iv)
2. A-(i), B-(ii), C-(iii), D-(iv)
3. A-(iii), B-(ii), C-(iv), D-(i)
4. A-(ii), B-(i), C-(iv), D-(iii)
Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks.
A | B | C | D | |
1. | Rock minerals | Detritus | Litter fall | Producers |
2. | Litter | Producers | Rock minerals | Detritus |
3. | Detritus | Rock minerals | Producers | Litter fall |
4 | Producers | Litter fall | Rock minerals | Detritus |
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 |
Which one of the following processes during decomposition is correctly described?
1. | Humanification-Leads to the accumulation of a dark-coloured substance in humans which undergoes microbial action at a very fast rate |
2. | Catabolism-Last step decomposition under fully anaerobic condition |
3. | Leaching-Water soluble inorganic nutrients rise to the top layers of the soil |
4. | Fragmentation-Carried out by organisms such as earthworms |
Secondary productivity is the rate of formation of new organic matter by:
1. Parasite
2. Consumer
3. Decomposer
4. Producer
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