Sun is not a source of energy is this ecosystem.

The dominant second trophic level, in a lake ecosystem, is

Which of the following are consumers of second order

$...A...$ is required for higher primary productivity. $...B...$ have the lowest primary productivity as the soil is deficient in moisture.

Choose the correct option for $\mathrm{A}$ and $\mathrm{B}$

Which of the following are called key industry animals?

Which one of the following system constitutes the primary producers