Class 6 NCERT Solutions Science Chapter 5 - Body Movements
Body Movements Exercise 57
Solution 1
1.
(a) movement
(b) Skeleton
(c) Hinge
(d) Muscle
Concept insight: Recall the concept of human body and its movement.
Solution 2
2.
(a) False
Concept insight: Different types of organisms have different locomotion and movements patterns. For example - birds fly, humans have bipedal locomotion, and animals have quadrupedal locomotion.
(b) False
Concept insight: Cartilages are flexible and less rigid than bones because the amount of calcium and phosphorus in cartilages is less than bones.
(c) False
Concept insight: Finger bones also have joints.
(d) True
Concept insight: Yes, fore arm has two bones radius and ulna.
(e) True
Concept insight: Outer skeleton of cockroaches is made up of a protein called chitin.
Solution 3
Concept insight: Important from Exam Point of View.
Solution 4
(a) Ball and socket joint is a movable joint. It consists of a bone that has a round head, which fits into a cup like depression of another bone. This helps the bone to rotate freely. Examples of such joints are hip and shoulder joints.
Concept insight: Ball and socket joint allows movement in all directions.
(b) Lower jaw bone (Mandible bone) is the only skull bone that is movable.
Concept insight: Rest all the skull bones are fused with each other except lower jaw bone.
(c) The elbow has a hinge joint. This type of a joint allows the movement in one plane only. Therefore, our elbow cannot move backwards.
Concept insight: A hinge joint allows the movement in only one direction.