Eco system practice · Mixed difficulty

Size of organism finally reduces at higher trophic level in

Which one option is incorrectly matched regarding biological magniècation of DDT in aquatic ecosystem.

In ecosystem at which trophic level human are placed :

a. may be second trophic level

b. may be third trophic level

c. may be first trophic level

d. may be fourth trophic level

Assertion: Pyramid of energy may be upright or inverted.
Reason: Only 20% of energy goes to next trophic level.

In primary succession in water, the pioneer species are

Assertion: Secondary succession always involves a predictable species sequence and ends up with the same climax community as existed prior to the disturbance.
Reason: A pond never be considered as a self-sustained ecosystem as it lacks all the structural and functional components that work as a unit in an ecosystem.

Phosphorus is required for making
I. shell
II. bones
III. teeth
Choose the correct option

Assertion (A): In a terrestrial ecosystem, detritus food chain is a major conduit for energy flow.

Reason (R): Solar energy is direct source of energy supply in detrirus food chain.

If $C{O_2}$ is removed totally from the biosphere, which organisms will be affected first?

After the primary producer level in an ecosystem;

An ecosystem is

In an ecosystem the rate of production of organic matter by producers which is available to herbivores is

In the phosphorus cycle, weathering makes phosphate available first to

Which specialised cell provides interconnectivity for air spaces?

The pyramid of biomass will be inverted in the ecosystem of

Consider the following statements about food web
I. One organism hold more than one position
II. The flow of energy is very difficult to calculate
III. Instead of straight line it is a series of branching lines
IV. Competition is amongst the members of same and different trophic levels
Which of the statements given above are correct?

The tiger biomass is 10 kg in grass-deer-tiger food chain. The grass biomass will be

In an ecosystem if the Net Primary Productivity (NPP) of first trophic level is $100 x\left(\mathrm{kcal} \mathrm{~m}^{-2}\right) \mathrm{yr}^{-1},$ what would be the GPP (Gross Primary Productivity) of the third trophic level of the same ecosystem?

A complex of several species and communities in various stages of succession maintained under similar climatic conditions is known as:

Assertion: Phosphorus cycle is an imperfect cycle as a sufficient amount of phosphorus combines with ${Al}^{3+}, {Fe}^{2+}$ and ${Ca}^{2+}$ to form insoluble and unavailable salts.

Reason: Phosphate circulates in abiotic environment in both lithosphere and in atmosphere.

Which of the following features would be characteristic of oceans but not of freshwater ecosystems?

Rabbits eats grass and other plants to survive, but they do not eat animals. Refer the best category for rabbits?

The lentic ecosystem includes

The products of decomposition process are

The correct sequence of food chain is

The process of accumulation of a dark coloured amorphous substance that is highly resistant to microbial action and undergoes decomposition at an extremely slow rate is called

Pyramid of energy in ecosystem is

In a food chain, the total amount of living material is depicted by

The amount of nutrients, such as carbon, nitrogen, phosphorus and calcium present in the soil at any given time, is referred as:

During ecological succession: