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

Which of the following is the correct sequence for primary succession in water (hydrarch succession)?

Which of the following are known as the 'pioneer species' in primary succession?

Identify the likely organisms $(1), (2), (3)$ and $(4)$ in the food web shown below.

What will happen to an ecosystem if:
$(a)$ All producers are removed;
$(b)$ All organisms of herbivore level are eliminated; and
$(c)$ All top carnivore population is removed?

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.