Question

Describe in brief the movement of snakes, cockroaches, snails, earthworms, and fish. [5 MARKS]

Answer 1

Animal movements: 1 Mark each

Snakes :
Snakes have a backbone and many interconnected muscles that help them to slither. They have muscles connecting the backbone, ribs and skin. Snakes move in a loop-like, zig-zag manner. They cannot move in a straight line, and have difficulty in moving on very smooth surfaces.

Cockroaches :
Cockroach is an arthropod with six jointed legs. These legs aid in walking, and two pairs of wings are used to fly. A cockroach moves its legs with the help of muscles near the limbs. It uses its breast muscles to move its wings and fly.

Snails :
Snail moves with the help of a single muscular foot. The under surface of the foot is lubricated with mucus which helps the snail to move easily. The rhythmic contractions and relaxations of the foot brings about a moving action in the body. The entire body except the foot lies inside the shell.

Earthworms:
Earthworms move with help of tiny, stiff hair-like projections called bristles. Every segment of the earthworm's body possesses "setae" which help in their movement. They move forward by repeated contractions and relaxations of their muscles in the skin. A slimy substance secreted by the earthworm helps in its movement.

Fish:
Fish possess a streamlined body which helps them to swim in water. They swim with the help of their fins and their tails. The tail flaps from side to side to propel in the right direction. Some fish, however, move by bending their bodies from one side to another in quick succession. This produces a thrust that helps it move forward.