Spongy or chancellors bone is present in vertebrae, ribs, skull, and epiphysis of long bones. They have

Options

A. Haversian canals
B. Trabeculae
C. Red bone marrow
D. Both (2) and (3)

Answer

To answer the question regarding spongy or cancellous bone, we can break down the information step by step:

### Step-by-Step Solution:

1. **Identify the Type of Bone**:
- The question refers to "spongy or cancellous bone," which is a type of bone found in various locations in the body, including vertebrae, ribs, skull, and the epiphysis of long bones.

**Hint**: Remember that cancellous bone is known for its porous structure.

2. **Understand the Structure of Cancellous Bone**:
- Cancellous bone has a unique structure characterized by a network of trabeculae (small rod-like structures) that create a spongy appearance.

**Hint**: Think of how a sponge looks; it has holes and is lightweight, similar to cancellous bone.

3. **Location of Cancellous Bone**:
- Cancellous bone is typically found at the ends of long bones, near joints, and within the interior of vertebrae. It is also present in the ribs and skull.

**Hint**: Recall that cancellous bone is found in areas where strength and lightness are required.

4. **Function of Cancellous Bone**:
- This type of bone is highly vascular and often contains red bone marrow, which is crucial for hematopoiesis (the production of blood cells).

**Hint**: Consider the role of bone marrow in blood cell production.

5. **Identify Key Components**:
- The primary anatomical and functional unit of cancellous bone is the trabeculae. The red bone marrow fills the spaces between these trabecular pores.

**Hint**: Trabeculae are essential for the structural integrity of cancellous bone.

6. **Review the Options**:
- The options provided were:
1. Haversian canal
2. Trabeculae
3. Red bone marrow
4. Both 2 and 3
- Since cancellous bone contains trabeculae and red bone marrow, the correct answer is "both 2 and 3."

**Hint**: Look for the components that are specific to cancellous bone.

### Final Answer:
The correct answer is **both 2 and 3** (trabeculae and red bone marrow).