Eco system practice · Mixed difficulty

The changes that occur in successive seral stages to reach a climax community are
I. changes in the diversity of species of organisms
II. increase in the number of species and organisms
III. increase in the total biomass
Choose the correct option

Sunken stomata are usually found in the leaves of

The process by which water soluble inorganic nutrients go down into the soil horizon and get precipitated as unavailable salts is called as

Assertion: Herbivores are also known as key industry animals because they convert plant matter into animal matter.

Reason: In an ecosystem decomposers play a vital role and they indirectly support the producers.

Ecological succession is a

Assertion: Green plants only show primary productivity.

Reason: Chemosynthesizers are responsible for primary productivity also.

Gross primary productivity is utilised by …A… in …B…
Choose the correct option for A and B

At each step of food chain when food energy is transferred from one trophic level to the next higher trophic level only about 10% of energy is passed onto next level. This is known as …A… given by …B… in …C… . Here A, B and C Refers to

Which of the following statements is not a major concern about our altering of the carbon cycle?

Greater primary productivity depends upon

Stratification occurs in

The pyramid of number of a parasitic food chain in tree ecosystem is

Assertion: The consequence of the second law of thermodynamics is the loss of biologically useful energy as heat with every energy transfer in a food chain.

Reason: Energy does not permanently remain trapped in any organism, it is either passed on to a higher trophic level or becomes available to detrivores and decomposers after the organism dies.

Humus is

Go through the following pairs and choose the correct pairs from the option given below
I. Nerium Sunken lower epidermis of leaves to stomata reduces loss of water
II. Calotropis Non-succulent Root cells with thickened
cell walls
III. Peperomia Leaf succulent Leaf epidermal cell, store
water
IV. Ammophila Dicot Curl their leaves to minimise loss of water
V. Tribulus Ephemeral Water is stored in stem

Consider the following ecosystem
I. Pond ecosystem II. Terrestrial ecosystem
III. Oceans ecosystem IV. Forest ecosystem
There are mainly three food chain in natural ecosystem’s grazing food chain, detritus food chain, parasite food chain
Find out which of the following will have grazing food chain?

Phosphorus is the major constituent of
I. biological membranes
II. nucleic acids
III. cellular energy transfer system
Choose the correct option

Assertion (A): Many environmental scientists believe amphibians, including frogs, are good biological indicators of broader ecosystem health.

Reason (R): These organisms have intermediate positions in food chains, have permeable skins, and typically biphasic lives (aquatic larvae and terrestrial adults).

Plant successions occurring in a sandy area is

…… temperature is required for the proper functioning of an enzyme. The most appropriate word

Primary succession occurs in?

The rate of biomass production per unit area over a time period by plants during photosynthesis is called

What is the medium by which carbon cycle takes place?

When the number of organisms at successive levels are plotted they assume the shape of a pyramid. This is called the pyramid of

Some of the nutrient cycles are labelled as below
I. Sulphur cycle II. Phosphorus cycle
III. Carbon cycle IV .Nitrogen cycle
Of these, the sedimentary cycle is represented by

Which one of the following is a gaseous cycle?

Identify the correct statements:

A. Detrivores perform fragmentation.

B. The humus is further degraded by some microbes during mineralization.

C. Water soluble inorganic nutrients go down into the soil and get precipitated by a process called
leaching.

D. The detritus food chain begins with living organisms.

E. Earthworms break down detritus into smaller particles by a process called catabolism.

Choose the correct answer from the options given below:

Assertion (A) : Petro plants yield Bio-diesel.
Reason (R) : Jatropa is rich in hydrocarbons.

Decomposers are

Assertion: Secondary succession is faster than primary succession.

Reason: Some soil or sediments are present.