Synovial joint occurs between

Options

A. pubic bones
B. centra of two vertebrae
C. two skull bones
D. humerus and ulna

Answer

To determine between which bones a synovial joint occurs, we need to analyze the options provided:

1. **Pubic Bone**: The pubic bones are connected by a cartilaginous joint known as the pubic symphysis. This type of joint allows for limited movement and is not classified as a synovial joint.

2. **Center of Two Vertebrae**: The joints between vertebrae are also cartilaginous joints, specifically intervertebral discs, which allow for slight movement but do not qualify as synovial joints.

3. **Two Skull Bones**: The joints between skull bones are known as sutures, which are fibrous joints. These joints are immovable and therefore are not synovial joints.

4. **Humerus and Ulna**: The humerus (upper arm bone) and ulna (one of the forearm bones) form the elbow joint, which is a classic example of a synovial joint. This joint allows for a wide range of movement and is characterized by the presence of a synovial cavity filled with synovial fluid.

Based on this analysis, the answer to the question is:

**The synovial joint occurs between the humerus and ulna.**