NCERT Solutions For Class 6 Science Chapter – 8
Q1. Fill in the blanks:
- Joints of the bones help in the _________ of the body.
- A combination of bones and cartilage forms the _____ of the body.
- The bones at the elbow are joined by a ______ joint.
- The contraction of the ______ pulls the bone joint.
Solution:-
- Movement
- Skeleton
- Hinge
- Muscles
Q2. Indicate the true and false among the following sentences.
- The movement and locomotion of all animals is exactly the same. ()
- The cartilage are harder than bones. ()
- The finger bones do not have joints. ()
- The fore arm has two bones. ()
- Cockroaches have an outer skeleton, ()
Answer:-
- False
- False
- False
- True
- True
Q3. Match the items in Column 1 with one or more items of Column 11.
Answer:-
Column 1 | Column 11 |
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 1 | Column 11 |
Upper Jaw | Is an immovable joint |
Fish | Have fins on the body, have a streamlined body |
Ribs | Protect the heart |
Snail | Has an outer skeleton and shows very slow movement |
Cocokroach | Has an outer skeleton and can fly in the air. |
Q4. Answer the following:
- What is a ball and socket joint ?
- Which of the skull bones are movable ?
- Why can our elbow not move backwards ?
Answer:-
- The rounded end of the bone fits into the cavity (hollow space) of the other bone. Such a joint allows movement in all directions which is called ball and socket joint.
- Lower Jaw
- Our elbow cannot move backwards because it has hinge joints which only allow back and forth movement.