Skull bones are

Options

A. Replacing bones
B. Investing bones
C. Sesamoid bones
D. Irregular bones.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Skull Bones**: The skull is composed of two main sets of bones: cranial bones and facial bones.

2. **Cranial Bones**: There are 8 cranial bones in the human skull. These bones form the protective case around the brain.

3. **Facial Bones**: In addition to the cranial bones, there are 14 facial bones. These bones form the structure of the face.

4. **Total Number of Skull Bones**: When you add the cranial bones (8) and the facial bones (14), the total number of bones in the skull is 22.

5. **Surgical Context**: A craniotomy is a surgical procedure where a section of the skull is removed to access the brain. The piece that is removed is referred to as a "bone flap."

6. **Replacing the Bone Flap**: After the surgical procedure, the bone flap is usually replaced using tiny plates and screws to secure it back in place. This process involves "replacing bones."

7. **Conclusion**: Therefore, the skull bones consist of 22 bones in total, comprising 8 cranial bones and 14 facial bones.

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