Grasslands can support greater grazing rates by herbivores than forests because:
(1) Grasslands receive more sunlight
(2) The net production of grasslands is greater
(3) Grasslands produce less woody plant tissue
(4) More of the grassland production is above ground
The amount of energy reaching an upper trophic level is determined by:
1. Net primary production
2. Net primary production and the efficiencies with which food energy is converted to biomass
3. Gross primary production
4. Gross primary production and the efficiencies with which food energy is converted to biomass
Fill in the blanks, in the following simplified model of a nutrient cycle:
1 2 3 4 5
(1) Producers Detritus Soil solution Decomposition Weathering
(2) Producers Detritus Soil solution Weathering Decomposition
(3) Producers Soil solution Detritus Decomposition Weathering
(4) Producers Soil solution Detritus Weathering Decomposition
The given figure best represents:
(1) Pyramid of number in parasitic food chain
(2) Pyramid of biomass in forest ecosystem
(3) Pyramid of number in grassland ecosystem
(4) Pyramid of number in forest ecosystem
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:
1. | Catabolism → Fragmentation → Leeching → Humification → Mineralization |
2. | Catabolism → Fragmentation → Humification → Leeching → Mineralization |
3. | Fragmentation → Humification → Catabolism → Leeching → Mineralization |
4. | Fragmentation → Leeching → Catabolism → Humification → Mineralization |
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
The amount of biomass or organic matter produced per unit area over -a time period by plants during photosynthesis is called primary production, which is expressed as:
(1) g m−2
(2) kcal m−2
(3) (kcal m−2) yr−1
(4) Both (1) and (2)
An ecosystem, which can be easily damaged, but can recover after some time if damaging effect stops will be having:
(1) High stability and high resilience
(2) Low stability and high resilience
(3) High stability and low resilience
(4) Low stability and low resilience
During the stages of succession in a given ecosystem the following changes in characteristics may be observed:
Characteristic | Stages in ecosystem development | |
Early | Late | |
A. Total matter | Low | High |
B. Species diversity | Low | High |
C. Size of organism | Small | Large |
D. Productivity | Low | High |
E. Food chains | Short | Long |
Which one of the characteristics, A, B, C, D or E is responsible for the apparent high degree of stability associated with a climax ecosystem?
(1) B
(2) D
(3) A
(4) E