Observe the following picture. Write the answers of the following questions :[Fig. A: a fish with a spindle-shaped body, fins and a tail fin. Fig. B: a pigeon with feathers, wings, a beak and scaly legs.](a) Identify the class of animals shown in abo…

Answer: (a) Fig. A belongs to class Pisces and Fig. B to class Aves. (b) Both have a spindle-shaped (streamlined) body, paired appendages modified for movement (fins and wings), a tail and a covering over the body, and both lay eggs. (c) Because they differ in their breathing organs, body covering, heart, temperature regulation and method of reproduction.

(b) Similarities (adaptations): the streamlined body reduces resistance while moving through air or water; the paired appendages (pectoral fins in the fish, wings in the bird) are used for movement; the tail helps in steering; the body covering (scales or feathers) protects the body; both are egg-laying animals.

(c) Differences: the fish breathes by gills, has scales and fins, a two-chambered heart and is cold-blooded, and its eggs are laid in water without a shell. The bird breathes by lungs with air sacs, has feathers and wings, a four-chambered heart, is warm-blooded and lays eggs with a hard shell on land. Hence they are placed in different classes.