Body Movements | Chapter 8 | Class 6 | Science | NCERT
Exercise
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.
2. Indicate true (T) and false (F) among the following sentences.
(a) The movement and locomotion of all animals are exactly the same. ( )
(b) The cartilages are harder than bones. ( )
(c) The finger bones do not have joints. ( )
(d) The forearm has two bones. ( )
(e) Cockroaches have an outer skeleton. ( )
Answer:
a) False
b) False
c) False
d) True
e) True
3. 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 a streamlined body |
| Ribs | Protect the heart |
| Snail | Has an outer skeleton andShows very slow movement |
| Cockroach | Has an outer skeleton andCan fly in the air |
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 one bone fits into the cavity (hollow space) of the other bone. Such a joint allows movements in all directions, which is called a ball and socket joint.
b) Lower jaw
c) Our elbow cannot move backwards because it has hinge joints which only allow back-and forth-movement.
NCERT Class 6 Science
Chapter 1: Food: Where Does It Come From?
Chapter 4: Sorting Materials and Groups
Chapter 5: Separation of Substances
Chapter 7: Getting to Know Plants
Chapter 9: The Living Organisms and Their Surroundings
Chapter 10: Motion and Measurement of Distances
Chapter 11: Light, Shadows and Reflections