Various Simple Animals

In earthworm, coelom is encompassed by two sets of muscles in the body wall.

• T

• F

Longitudinal muscles of earthworm are repeated in segments and run the length of the body.

• T

• F

Answer explanation

Circular muscles of earthworm are repeated in segments and run the length of the body.

In earthworm, longitudinal and circular muscles are opposite in action.

• T

• F

Long and bristle like structures called setae are on the underside of the worm’s body.

• T

• F

Answer explanation

Short and bristle like structures called setae are on the underside of the worm’s body.

In the locomotion of earthworm, circular muscles relax and longitudinal muscles contract in the anterior end.

• T

• F

Answer explanation

In the locomotion of earthworm, circular muscles contract and longitudinal muscles relax in the anterior end.

In the second step of earthworm locomotion, the front end of the body extends.

• T

• F

The flexor and extensor muscles are agonist muscles.

• T

• F

Answer explanation

The flexor and extensor muscles are antagonistic muscles.

In jumping of a grasshopper, flexor muscles bend a joint and extensor muscles.

• T

• F

The rear legs of a grasshopper are long and muscular and are adapted for hopping or jumping.

• T

• F

In grasshopper, elevator and depressor muscles are located inside the endoskeleton of the thorax.

• T

• F

Answer explanation

In grasshopper, elevator and depressor muscles are located inside the exoskeleton of the thorax.