Which is the simplest synovial joint ?

Options

A. Ball and socket
B. Hinge joint
C. Saddle joint
D. Gliding joint

Answer

### Step-by-Step Solution:

1. **Understanding Synovial Joints**:
- Synovial joints, also known as diarthroses, are characterized by their ability to allow free movement. They contain synovial fluid, which lubricates the joint and facilitates smooth movement between the bones.

2. **Types of Synovial Joints**:
- There are six major types of synovial joints:
- **Ball and Socket Joint**: Allows movement in all directions (e.g., shoulder and hip joints).
- **Hinge Joint**: Allows movement in one direction, similar to a door hinge (e.g., elbow and knee joints).
- **Condyloid Joint**: Allows movement but no rotation (e.g., joints in fingers and jaw).
- **Pivot Joint**: Allows rotational movement (e.g., joint between the radius and ulna).
- **Gliding Joint**: Allows limited movement, characterized by smooth surfaces that can slide over one another (e.g., joints in the wrist).
- **Saddle Joint**: Allows movement back and forth and side to side but does not permit rotation (e.g., joint at the base of the thumb).

3. **Identifying the Simplest Synovial Joint**:
- Among the types of synovial joints, the saddle joint is identified as the simplest. It allows for limited movement compared to other joints but is characterized by its unique structure that permits movement in two planes without rotation.

4. **Conclusion**:
- Based on the analysis of the types of synovial joints, the simplest synovial joint is the **saddle joint**.

### Final Answer:
The simplest synovial joint is the **saddle joint**.

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