Categorise the following plants into hydrophytes, halophytes, mesophytes and xerophytes. Give reasons for your answers.

a. Salvinia

b. Opuntia

c. Rhizophora

d. Mangifera

Why do submerged plants receive weaker illumination than exposed floating plants in a lake?

In a seashore, the benthic animals live in sandy, muddy and rocky substrata and accordingly developed the following adaptations.

a. Burrowing

b. Building cubes

c. Holdfasts / peduncle

Find the suitable substratum against each adaptation.

In a pond, we see plants which are free-floating; rooted–submerged; rooted emergent; rooted with floating leaves. Write the type of plants against each of them.

The density of a population in a habitat per unit area is measured in different units. Write the unit of measurement against the following:

a. Bacteria _______________

b. Banyan _______________

c. Deer _______________

d. Fish _______________