In humans; femur and humerus like long bones function in

Options

A. support
B. support erythrocyte and leucocyte synthesis
C. support, and erythrocyte synthesis
D. erythrocyte formation

Explanation

To answer the question regarding the functions of long bones like the femur and humerus in humans, we can break it down into several steps:

### Step-by-Step Solution:

1. **Identification of Long Bones**:
- The femur is the thigh bone, and the humerus is the bone in the upper arm. Both are classified as long bones in the human body.

2. **Function of Support**:
- Long bones provide structural support to the body. They serve as a framework that supports the muscles and other tissues. The attachment of muscles to these bones allows for movement and stability.

3. **Hematopoiesis (Blood Cell Formation)**:
- Long bones contain bone marrow, which is crucial for the production of blood cells. The bone marrow houses pluripotent stem cells that can differentiate into various types of blood cells, including:
- Erythrocytes (Red Blood Cells) - involved in oxygen transport.
- Leukocytes (White Blood Cells) - involved in immune response.
- Platelets - involved in blood clotting.

4. **Conclusion**:
- Therefore, the functions of long bones like the femur and humerus include providing support to the body and facilitating the synthesis of blood cells through the bone marrow.

### Final Answer:
In humans, the femur and humerus, like other long bones, function primarily in providing structural support and in the synthesis of blood cells (erythrocytes and leukocytes) through the bone marrow.

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