You are here
๐ฌ Think about it
Your elbow only bends one way, but your shoulder swings all around. Why can some parts move freely and others not? The answer lies in the joints. Let us observe our own movements first.
In this Activity, we will move different body parts and observe which movements each one can make.
Procedure
Move different parts of your body and observe what movement(s) each one can make. Record your findings in Table 3.5.
Table 3.5 — Different types of movements our body can make
| Body parts | Complete rotation | Partial rotation | Bending | Turning, side-raising, up-down or any other movement |
|---|---|---|---|---|
| Elbow | No | No | Yes | Up-down bending only |
| Shoulder | Yes | Yes | Yes | All directions |
| Knee | No | No | Yes | Up-down bending only |
| Neck | No | Yes | Yes | Side to side turning |
| Fingers | No | No | Yes | Bending |
| Toes | No | No | Yes | Bending |
| Wrist | No | Yes | Yes | Partial rotation |
Explanation
Some parts move easily in many directions, while others move only one way. The difference is due to the types of joints present. A joint is a junction between two or more bones. Joints allow movement but cannot move bones on their own — muscles do that.
โ Summary
- Move each body part.
- Note how it moves.
- Some move freely, some don't.
- Joints decide the movement.
What is a joint?
- A joint is a junction between two or more bones.
- Joints allow movement of the body.
- They cannot move the bones on their own.
- The type of joint decides what movement is possible.
Example:
The elbow joint lets the arm bend, while the shoulder joint lets it swing around.
Important Points
- Different body parts move in different ways.
- A joint is a junction between two or more bones.
- The type of joint decides the movement allowed.
โ Test Yourself
-
What is a joint?
View Answer
A junction between two or more bones. -
Can joints move bones on their own?
View Answer
No — muscles move the bones; joints only allow the movement. -
Why does the elbow move differently from the shoulder?
View Answer
They have different types of joints.
Important Definitions
- Joint — a junction between two or more bones that allows movement.
