1. Long bones
2. Short bones
3. Irregular bones
4. Flat bones

They have a relatively flat, thin shape and are composed of two layers of compact bone tissue with a layer of spongy bone tissue in between. These bones play important roles in the protection, support, and production of blood cells.

Structure of Flat Bones:

Flat bones are characterised by their flat, plate-like shape. They typically consist of two layers of compact bone tissue on the outer surfaces, which enclose a layer of spongy bone tissue in the middle. The spongy bone contains bone marrow and blood vessels.

➤Flat bone examples:

skull bones, scapulae (shoulder blades), sternum (breastbone), ribs, and certain bones of the pelvis.

Functions of Flat Bones:

1. Protection: Flat bones provide protection to underlying vital organs. For example, the skull bones protect the brain, while the ribs and sternum protect the heart and lungs.

2. Hematopoiesis: The spongy bone tissue within flat bones is involved in hematopoiesis, which is the process of producing blood cells. Red and white blood cells, as well as platelets, are produced within the bone marrow of flat bones.

3. Support and Attachment: Flat bones provide a broad surface area for the attachment of muscles, tendons, and ligaments. Muscles that are involved in movement and posture depend on flat bones for attachment points.

4. Mineral Storage: Like other types of bones, flat bones also play a role in storing minerals like calcium and phosphorus. These minerals are vital for various physiological processes, including bone health and muscle contraction.

5. Temperature Regulation: Blood flow within flat bones helps regulate body temperature.

Conclusion:

Flat bones have a unique structure that contributes to their functions in protection, support, blood cell production, mineral storage, and thermal regulation. Their flat and broad shape makes them well-suited for these roles, and they play an essential part in the overall function of the skeletal system and the body as a whole.