The joint of radio-ulna with the upper arm is called a

Options

A. Hinge joint
B. Pivot joint
C. Socket joint
D. None of these

Answer

To solve the question regarding the joint of the radio-ulna with the upper arm, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Bones Involved**:
- The question mentions the "radio-ulna" which refers to the radius and ulna bones in the forearm.
- The "upper arm" refers to the humerus bone.

2. **Understand the Joint Type**:
- The joint formed between the radius and ulna with the humerus is essential for arm movement.
- We need to determine the type of joint that allows for the specific movement between these bones.

3. **Evaluate Joint Types**:
- **Hinge Joint**: Allows movement in one plane, similar to the motion of a door hinge (back and forth).
- **Pivot Joint**: Allows rotational movement around a single axis.
- **Socket Joint**: Allows for multi-directional movement (like the shoulder joint).
- **None of These**: Would apply if none of the options fit.

4. **Determine the Correct Joint**:
- The joint between the radius and ulna with the humerus primarily allows for flexion and extension (bending and straightening), which is characteristic of a hinge joint.

5. **Conclusion**:
- Based on the analysis, the joint of the radio-ulna with the upper arm is classified as a **hinge joint**.

### Final Answer:
The joint of radio-ulna with the upper arm is called a **hinge joint**.

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