23. Match the following from Column A
with Column B.
Column A
(a) Earthworm
(b) Fish
(c) Snake
(d) Cockroach
Column B
(i) Breast is connected with 3 pairs of legs
and 2 pairs of wings.
(ii) Crawl on the ground by alternately
looping sideways.
(iii) Swim by forming loops alternately on
two sides of body
(iv) Move by alternate extension and
contraction of the body. *
(2 Points)
(a)-(ii); (b)-(iii); (c)-(iv); (d)-(i)
(a)-(iv); (b)-(iii); (c)-(ii); (d)-(0)
(a)-(iv); (b)-(ili); (c)-(i); (d)-(ii)
(a)-(iii); (b)-(iv); (C)-(ii); (d)-0
Answers
Answer:
Bones in our body form the framework that supports the whole body. This framework is called the skeleton.
Our skeleton is made up of many pieces of bones and cartilages.
There are about 650 muscles attached to the various bones in our body.
The bones are hard.
Cartilages are comparatively soft and elastic.
Functions of skeleton
Skeleton system gives support to the body.
It protects the inner organs.
Together with muscles, it gives the body its shape.
Red blood cells and some white blood cells are produced in the marrow of the bone.
7. X-ray machine : We can get photographs of bones by a machine called X-ray machine. Doctors use these photographs to examine the injuries and diseases of bones.
8. The bones in our body vary in their sizes and shapes. Different types of bones have different functions.
9.The skull : The skull has two main parts :
Cranium : The bones of cranium are flat. They are held firmly like a zipper, it covers and protects the brain.
Facial bones : The facial bones comprise the upper jaw, lower jaw and few other bones. The lower jaw is movable. The movement of lower jaw enables us to eat, talk and sing.
10. Eye sockets : The skull also includes a pair of eye sockets. These form a safe pocket for eyes.
11. The backbone : Backbone or vertebral column is composed of 33 small, ring like vertebrae joined end to end. It forms a hollow bony tube. The main nerve cord passes through it.
12. The chest bones : 12 pairs of ribs along with backbone make a cone shaped cage which protect the heart.
13. The shoulder bones :The shoulder bone is formed by the color bone and the shoulder blade. The shoulder bones are flat and large. They help in forming joint with long bones.
14. Hip bones :The hip bone is formed by the fusion of three bones. Like shoulder bones, the hip bones are also flat and large. They help in forming joints with long bones. Together with the last two parts of backbone it forms a large bony bowl called pelvis.
15. Bones of hands and legs : Bones of arms, thighs etc., are long. They give strength to our body. Bones of fingers and toes are short. They help us in holding things. The hands and legs are constructed in same pattern as described below.
Parts of Hand Part of Leg
No. of Bones
Upper arm
Fore arm
Wrist
Palm
Fingers
Thigh
Lower leg
Ankle
Foot
Toe One long bone
Two long bones
Several small bones
Five bones
Each has three small bones
16. Bone joints : The place where two or more bones meet together is called a joint. In our body five types of joints are present namely :
Fixed joints which do not allow movement, e.g. joints of cranium.
Ball and socket joint allows movement in all direction e.g. joints between upper arm and shoulder, thigh and hip.
Pivotal joint allows movement in many planes e.g. skull makes such joint with first two vertebrae.
Hinge joints allow movements only in one direction e.g. fingers, the knee etc.
Gliding joints allow only a limited amount of movement e.g. joints of backbone.
17. Muscles : The bones are moved by alternate contractions and relaxations of two sets of muscles.
18. Tendons join muscles to the bones.
19. Ligamentjoins two bones.
20. Bristles : Bristles are hair like structure, connected with muscles. The bristles help to get a good grip on the ground.
21. Cavity : It is the hollow space in one bone, into which the other bone fits. Such joint allows movements in all directions.
22. Gait of animals : Some animals do not have bones. They have muscles which help to extend and shorten the body. During movement, animal first extends the front part of the body, keeping the rear position fixed to the ground. After that animal fixes the front and releases the rear end. Now animal shortens the body and pull the rear end forward. During this practice animal move forward by a small distance.
23. Rib cage : Ribs join the chest bone and the backbone together to form a box. This is called rib cage.
24. Locomotion
Answer:
(a)ii
(b)-iii
(c)-iv
(d)i