Ecosystem

An association of individuals of different species living in the same habitat and having functional interactions is -

1. Ecological niche
2. Ecosystem
3. Population
4. Biotic community

Most animals that live in deep oceanic waters are -

1. primary consumers
2. detritivores
3. tertiary consumers
4. secondary consumers

During ecological succession :

1. the establishment of a new biotic community is very fast in its primary phase.
2. the numbers and types of animals remain constant.
3. the changes lead to a community that is in near equilibrium with the environment and is called pioneer community
4. the gradual and predictable change in species composition occurs in a given area

In which of the following both pairs have correct combination?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

The mass of living material at a trophic level at a particular time is called :

1. Net primary productivity
2. Standing state
3. Standing crop
4. Gross primary productivity

Vertical distribution of different species occupying different levels in a biotic community is known as :

1. Stratification
2. Pyramid
3. Divergence
4. Zonation

Secondary Succession takes place on/in :

1. Newly created pond
2. Newly cooled lava
3. Bare rock
4. Degraded forest

In an ecosystem the rate of production of organic matter during photosynthesis is termed as :

1. Secondary productivity
2. Net Productivity
3. Net primary productivity
4. Gross primary productivity

Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks. [figure]

1. A Detritus, B Rock minerals, C Producer, D Litter fall
2. A Litter fall, B Producers, C Rock minerals, D Detritus
3. A Rock minerals, B Detritus, C Litter fall, D Producers
4. A Producers, B Litter fall, C Rock minerals, D Detritus

If 20 J of energy is trapped at producer level, then how much energy will be available to peacock as food in the following chain? Plant mice snake peacock

1. 0.0002 J
2. 0.002 J
3. 0.2 J
4. 0.02 J

Natural reservoir of phosphorus is :

1. Fossils
2. Rock
3. Sea water
4. Animal bones

Secondary productivity is rate of formation of new organic matter by :

1. Parasite
2. Decomposer
3. Producer
4. Consumers

Which one of the following processes during decomposition is correctly described ?

1. Catabolism – Last step in the decomposition under fully anaerobic condition
2. Leaching – Water soluble inorganic nutrients rise to the top layers of soil
3. Fragmentation – Carried out by organisms such as earthworm
4. Humification – Leads to the accumulation of a dark coloured substance humus which undergoes microbial action at a very fast rate

Which one of the following is a primary consumer in maize field ecosystem ?

1. Phytoplankton
2. Lion
3. Grasshopper
4. Wolf

When man eats fish which feeds on zooplankton which have eaten small plants, the producer in the chain is :

1. Zooplankton
2. Fish
3. Small plants
4. Man

The rate of formation of new organic matter by rabbit in a grassland, is called :

1. Net productivity
2. Gross primary productivity
3. Secondary productivity
4. Net primary productivity

The second stage of hydrosere is occupied by plants like

1. Vallisneria
2. Typha
3. Azolla
4. Salix

Identify the likely organisms (a), (b), (c) and (d) in the food web shown below : [figure]

1. (a) deer, (b) rabbit, (c) frog, (d) rat
2. (a) squirrel, (b) cat, (c) rat, (d) pigeon
3. (a) dog, (b) squirrel, (c) bat, (d) deer
4. (a) rat, (b) dog, (c) tortoise, (d) crow

Which one of the following is not a gaseous biogeochemical cycle in ecosystem?

1. Sulphur cycle
2. Nitrogen cycle
3. Phosphorus cycle
4. Carbon cycle

Identify the possible link "A" in the following food chain: Plant insect frog "A" Eagle

1. Wolf
2. Rabbit
3. Cobra
4. Parrot

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels? [figure]

1. Level PC is "rats" and level SC is "cats"
2. Level PP is "phytoplankton" in sea and "whale" on top level TC
3. Level PP is "pipal trees" and the level SC is "sheep"
4. Level PC is "insects" and level SC is "small insectivorous birds"

Which one of the following is not a functional unit of an ecosystem?

1. Energy flow
2. Decomposition
3. Productivity
4. Stratification

The upright pyramid of numbers is absent in

1. Pond
2. Grassland
3. Lake
4. Forest

Which one of the following animals may occupy more than one trophic level in the same ecosystem at the same time?

1. Lion
2. Frog
3. Goat
4. Sparrow

Both, hydrarch and xerarch successions lead to:

1. Xeric conditions
2. Excessive wet conditions
3. Highly dry conditions
4. Medium water conditions

The breakdown of detritus into smaller particles by earthworm is a process called

1. Fragmentation
2. Catabolism
3. Mineralisation
4. Humification

Mass of living matter at a trophic level in an area at any time is called :

1. Humus
2. Detritus
3. Standing state
4. Standing crop

Of the total incident solar radiation the proportion of PAR is

1. About 60%
2. More than 80%
3. Less than 50%
4. About 70%

Which one of the following statements is correct for secondary succession?

1. It follows primary succession
2. It occurs on deforested site
3. It is similar to primary succession except that it has a relatively fast pace.
4. It begins on a bare rock.

Which one of the following statements for pyramid of energy is incorrect, whereas the remaining three are correct?

1. It shows energy content of different trophic level organisms
2. It is upright in shape
3. It is inverted in shape
4. Its base is broad