Secondary productivity means
(1) Rate of formation of organic matter by producer.
(2) Rate of formation of new organic matter by consumers.
(3) Rate of formation of inorganic matter by producer
(4) Rate of formation of inorganic matter by consumer
Match Column-I with Column-II and select the correct option
Column-I Column-II
a. Fragmentation (i) Break down of detritus into smaller particles
b. Leaching (ii) Precipitation of water soluble nutrients as unavailable salt
c. Catabolism (iii) Degradation of detritus by bacterial and fungal enzymes
1. a. — (i) ; b. — (ii) ; c. — (iii)
2. a. — (ii) ; b. — (iii) ; c. — (i)
3. a. — (iii) ; b. — (ii) ; c. — (i)
4. a. — (iii) ; b. — (i) ; c. — (ii)
Humus is degraded by some microbes and release of inorganic nutrients occur by the process known as
(1) Fragmentation
(2) Leaching
(3) Humidification
(4) Mineralisation
Following are the two main structural features of an ecosystem
a. Species composition
b. Energy flow
c. Decomposition
d. Stratification
1. a. and d. 2. b. and c.
3. Only a. 4. b. and d.
Cycling of material in ecosystem is entirely dependent upon
(1) Producers and consumers.
(2) Primary producers and herbivores.
(3) Herbivores and carnivores
(4) Producers and decomposers.
The process of decomposition is in the following order
(1) CatabolismFragmentationLeachingHumificationMineralization
(2) CatabolismFragmentationHumificationLeachingMineralization
(3) FragmentationHumificationCatabolismLeachingMineralization
(4) FragmentationLeachingCatabolismHumificationMineralization
Net primary productivity
(1) For oceans is 60% of biosphere productivity
(2) Depends upon photosynthetic capacity of producers.
(3) Remains constant in temperate area throughout the year
(4) Is limited by light in marine habitats only
Most important climatic factors that regulate the rate of decomposition are
(1) Temperature and soil moisture.
(2) Soil pH and aeration
(3) Aeration and temperature
(4) Moisture and soil Ph
Gross primary productivity is
(1) Rate of which organic molecules are formed in an autotroph.
(2) Rate at which organic molecules are used up by an autotroph
(3) Storage of organic molecules in the body of an autotroph
(4) Rate at which organic molecules are transferred to next higher trophic level.
Which law is obeyed during energy flow in an ecosystem?
(1) First law of thermodynamics
(2) Second law of thermodynamics
(3) Third law of thermodynamics
(4) Both 1. and 2.
Find the incorrect statement
(1) In terrestrial ecosystem larger fraction of energy flow occurs through DFC
(2) In aquatic ecosystem a major conduit for energy flow is GFC
(3) Detritus food chain is not at all connected with grazing food chain at any level.
(4) Natural interconnection of food chain makes it a food web
A graphical representation known as ______is required to express food or energy relationship between organisms at different trophic levels.
(1) Ecological pyramid
(2) Standing state
(3) Ecological quadrilateral
(4) Standing crop
Find the correct statement
(1) Trophic level represents a functional level, not a species as such
(2) A given species never occupies more than one trophic level in the same ecosystem at the same time
(3) In most ecosystem, producers are less in number and biomass than the herbivores
(4) Pyramid of energy can never be upright
A food web
(1) Increases variety of food at each trophic level
(2) Delicately balances the inter-relations among organisms.
(3) Decreases variety of food but increases quantity of food at each trophic level
(4) Increases variety as well as quantity of food at each trophic level
Orderly and sequential changes in communities, parallel with the changes in the physical environment is known as
(1) Ecological succession.
(2) Extinction.
(3) Divergent evolution.
(4) Convergent evolution.
The entire sequence of communities that successively, change in a given area are called
Find out the total number of true statements from the following:
a. Primary succession is a very slow process, taking thousands of years for the climax to be reached.
b. All succession whether taking place in water or land, proceeds to a similar climax community, the mesic.
c. As succession proceeds, the number and types of animals and decomposers also change
d. Saprophytes are not given any place in the ecological pyramids even though they play a vital
role in the ecosystem.
1. One 2. Two
3. Three 4. Four
Amount of nutrients present in soil at any given time is referred as
Which of the following majorly regulates the amount of carbon in the atmosphere?
(1) Respiratory activities of the producers and consumers
(2) Decomposers
(3) Burning of fossil fuel
(4) Oceanic reservoir
What price tag did Robert Constanza put for fundamental ecosystem services?
Out of the total cost of various ecosystem services, the soil account for __________%, recreation and nutrient cycling constitute less than ___________% and climate regulation and habitat for wildlife account for about __________% each.
The two major differences between carbon and phosphorus cycles are
a. Atmospheric inputs of phosphorus through rainfall are much smaller than carbon inputs
b. Atmospheric inputs of phosphorus through rainfall are much greater than carbon inputs
c. Gaseous exchange of phosphorus between organism and environment is not negligible
d. Gaseous exchange of phosphorus between organism and environment is negligible
1. a. and b. 2. b. and c.
3. a. and d. 4. a. and c.
Read the given statements and choose the right option
a. The amount of living matter (biomass) present at every tropical level is called standing crop
b. Saprophytes do not form part of ecological pyramids
c. Ecological pyramid does not account the same species belonging to two or more trophic levels
d. Humus is reservoir of nutrients
1. All are correct
2. All are incorrect
3. Only d. is correct
4. a, d and c are correct
A major advantage of using YAC as a cloning vector over the plasmids is that :
1. it can replicate independently
2. it can be selected easily
3. it can accommodate larger inserts
4. it has multiple cloning sites
Triangular age pyramid represents
1. Expanding population.
2. Declining population.
3. Mature population.
4. Both 1. and 3.
Choose the incorrect match
1 |
Vertical distribution of different species occupying different levels |
- |
Stratification |
2 |
The most productive ecosystem |
- |
Sugarcane field |
3 |
The most limiting nutrient of marine ecosystem |
- |
Nitrogen |
4 |
Release of inorganic nutrients from humus during the process of decomposition |
- |
Mineralisation |
Each tropic level has a certain mass of living material at a particular time called
1. Standing crop 2. Standing state
3. GPP 4. NPP
Who coined the term ecosystem and defined it as the sum total of interactions between biotic and abiotic
components?
1. C. Mobius 2. A.G. Tansley
3. Forbes 4. Friederich
Detritus is
1. Dead raw material for decomposition.
2. Partially decomposed organic matter.
3. Dead remains of animals & plants.
4. Both 1 and 3
In aquatic ecosystem, major channel for energy flow is
1. | Grazing food chain. | 2. | Detritus food chain. |
3. | Auxiliary food chain. | 4. | Parasitic food chain. |