Q1. Fill in the blanks:

(a) Joints of the bones help in the _____________ if the body.

Answer: movement

(b) A combination of bones and cartilage forms the ___________ of the body.

Answer: skeleton

(c) The bones at the elbow are joined by a _________ joint.

Answer: hinge

(d) The contraction of the ____________pulls the bones during movement.

Answer: muscles

Q2. Indicate true (T) and false (F) among the following sentences.

(a) The movement and locomotion of all animals are exactly the same. ()

Answer: False

(b) The cartilages are harder than bones. ()

Answer: False

(c) The finger bones do not have joints. ()

Answer: False

(d) The fore arm has two bones. ()

Answer: True

(e) Cockroaches have an outer skeleton. ()

Answer: True

Q3. Match the items in column I with one or more items of column II

Column I	Column II
Upper jaw	Have fins on the body
Fish	Has an outer skeleton
Ribs	Can fly in the air
Snail	Is an immovable joint
Cockroach	Protect the heart
	Shows very slow movement
	Have a streamlined body

Answer:

Column I	Column II
Upper jaw	Is an immovable joint
Fish	Have fins on the body, have streamlined body
Ribs	Protect the heart
Snail	Shows very slow movement
Cockroach	Has an outer skeleton

Q4. Answer the following:

(a) What is a ball and socket joint?

Answer: Ball and socket joint is the rounded end of one bone fits into the cavity (hollow space) of the other bone. Such joint allows movement in all direction.

(b) Which of the skull bones are movable?

Answer: Only lower jaw is movable in skull.

(c) Why can our elbow not move backwards?

Answer: Our elbow does not move backwards because of the hinge-joint present in the elbow which allows only to move in only one direction (back to forth).