NCERT Solutions for Class 6 Science Chapter 8 Body Movements

Q.1 Fill in the blanks: (a) Joints of the bones help in the _____________ of the body.
(b) A combination of bones and cartilages forms the _______ of the body.
(c) The bones at the elbow are joined by a ______________________ joint.
(d) The contraction of the _____________ pulls the bones during movement.

Answer :

(a) Joints of the bones help in the movement of the body.
(b) A combination of bones and cartilages forms the skeleton of the body.
(c) The bones at the elbow are joined by a hinge joint.
(d) The contraction of the muscles pulls the bones during movement.

Q.2 Indicate true (T) and false (F) among the following sentences.
(a) The movement and locomotion of all animals is exactly the same. ( )
(b) The cartilages are harder than bones. ( )
(c) The finger bones do not have joints. ( )
(d) The fore arm has two bones. ( )
(e) Cockroaches have an outer skeleton. ( )

Answer :

(a) The movement and locomotion of all animals is exactly the same. (F )
(b) The cartilages are harder than bones. (F )
(c) The finger bones do not have joints. (F )
(d) The fore arm has two bones. ( T)
(e) Cockroaches have an outer skeleton. ( T)

Q.3 Match the items in Column I with one or more items of Column II.

Column I

Upper jaw
Fish
Ribs
Snail
Cockroach

Column II

Have fins on the body
Has an outer skeleton
Can fly in the air
is an immovable joint
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 a streamlined body
Ribs$?$Protect the heart
Snail $?$ Shows very slow movement
Cockroach $?$Has an outer skeleton

Q.4 Answer the following:
(a) What is a ball and socket joint?
(b) Which of the skull bones are movable?
(c) Why can our elbow not move backwards?

Answer :

(a) The rounded end of bone fits into the cavity of the other bone. Such a joint allows movements in all directions is called ball and socket joint.
(b) Lower jaw
(c) Elbow cannot move backwards because it has hinge joint which allows movement in only one direction.