Corals are:

Name the five classes of vertebrates. Compare any two on the basis of their $(i)$ Habitat,$(ii)$ Covering of skin,$(iii)$ Respiratory organs,$(iv)$ Chambers of heart,and $(v)$ Reproduction.

Write appropriate terms for the following:
$(i)$ Animals that are able to maintain a constant body temperature over a wide range of environmental temperatures.
$(ii)$ Animals which have a pseudocoelom.
$(iii)$ Plants which bear naked seeds.

An animal is dorsoventrally flattened,has three embryonic germ layers,and is acoelomate. Which phylum does it belong to? What are they commonly called? Give one example.

$(a)$ In which two ways do amphibians differ from fishes?
$(b)$ Identify the phylum of organisms having the following characteristics:
$(i)$ Pore-bearing animals and radial symmetry.
$(ii)$ Body spiny and radial symmetry.
$(c)$ Why do gymnosperms not require water for fertilization?

Classify the following organisms based on the absence $/$ presence of true coelom,i.e.,acoelomate,pseudocoelomate,and coelomate:
$(a)$ Scorpion
$(b)$ Sea anemone
$(c)$ Ascaris
$(d)$ Earthworm
$(e)$ Wuchereria
$(f)$ Nereis