Eco system practice · Mixed difficulty

A detrivore is

Decomposers of an ecosystem includes

Decomposition is

Ecological succession is

In the vast marine ecosystem, certain sea develop red colouration. This red colour is due to the presence of large population of which one of the following organisms?

Select the incorrect statement for ecological pyramid.

In hydrarch succession, the successional series progress from

Assertion: The pyramid of biomass indicates the decrease in biomass at each trophic level from base to apex.

Reason: Parasites have inverted pyramid for biomass.

In grazing food chain energy comes from

Given below are two statements
Statement I: Any calculation of energy content, biomass or numbers has to be include all organism at that trophic level.
Statement II: One must remember that the trophic level represents a functional level, not a species as such
Choose the correct answer from the option given below:

Which of the following statements are correct?
I. Least productive ecosystems are deserts and deep lakes
II. Sugarcane is the most productive crop
III. Most productive ecosystem is coral reef
Choose the correct option

Decomposition of organic matter is brought about by

Which of the following statements for pyramid of energy is INCORRECT, whereas remaining stands correct?

The organisms, which attack dead animals are

Productivity is the rate of production of biomass expressed in terms of
$\begin{array}{cccccccccccccccccccc} {\left( i \right)\,\left( {kcal\,{m^{ - 3}}} \right)\,y{r^{ - 1}}}&{\left( {ii} \right)\,{g^{ - 2}}y{r^{ - 1}}}&{\left( {iii} \right)\,{g^{ - 1}}y{r^{ - 1}}}&{\left( {iv} \right)\,\left( {kcal\,{m^{ - 2}}} \right)\,y{r^{ - 1}}} \end{array}$

Assertion: Capillary water is the readily available soil water to plants.
Reason: Capillary water is the thin film of water which is retained around soil particles.

Which of the following are the essential sources for releasing $C{O_2}$ in the atmosphere?
I. Burning of wood
II. Volcanic activity
III. Combustion of organic matter
IV. Fossil fuels
Choose the correct option

Green plants and green sulphur bacteria, prepare their organic food themselves with the help of sunlight, are known as

The ecological pyramid that is always upright

Identify the possible link “A” in the following food chain.
$\mathrm{Plant} \to \mathrm{Insect} \to \mathrm{Frog} \to 'A' \to \mathrm{Eagle}$

The pyramid of number in grassland ecosystem is:

It is an example of amphibious plant

Which of the following is false?

Consider the following statements about food chain
I. The transfer of energy from producers to top consumers through a series of organisms is called food chain
II. A food chain is always straight and proceeds in a progressive straight line
III. In a food chain, there is unidirectional flow of energy from sun to producers and subsequently to series of different types of consumers
Which of the statements given above are correct?

Consider the following statements about limitations of ecological pyramids
I. It never takes into account the same species belonging to two or more trophic levels
II. It assumes a simple food chain, which never exists in nature
III. In split of the vital role played by saprophytes/decomposers, they are not given any position in ecological pyramids
Which of the statements given above are correct?

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?
$\mathrm{Plant} \to \mathrm{mice} \to \mathrm{Snake} \to \mathrm{Peacock}$

If a predator is over exploitation its prey in a ecosystem then what might be consequences of this?

All the animals that depend on plants for food are called

Consider the following statements
I. In a food chain one organism holds only one position
II. In a food chain the flow of energy can be easily calculated
III. In food chain competition is limited to the members of same trophic level
Which of the statements given above are correct?

Identify the wrong pair of statements.
I) During plant succession, some species colonise an area and populations become more numerous,whereas
populations of other species decline and even disappear.

II) Both hydrarch and xerarch successions lead to mesic conditions.

III) Secondary succession is a slow process when compared to primary succession.

IV) In the successive seral stages, there is no change in the diversity of species of organisms.