Answer:
Periosteum, Compact Bone, Spongy Bone, Bone Marrow, Articular Cartilage, Medullary Cavity
Step-by-step explanation:
Periosteum: The outermost layer of a bone is called the periosteum. It is a tough, fibrous membrane that covers the bone's surface. The periosteum contains blood vessels, nerves, and connective tissue that nourish and support the bone.
Compact Bone: Beneath the periosteum lies a layer of compact bone, also known as cortical bone. Compact bone is dense and hard. It forms the main shaft or diaphysis of the long bone. Its structure consists of multiple layers of tightly packed mineralized matrix called lamellae, which contain collagen fibers. Compact bone provides strength and protection to the bone.
Spongy Bone: The interior of the bone, particularly at the ends and in the middle of long bones, contains spongy bone, also called cancellous or trabecular bone. Spongy bone has a porous, lattice-like structure composed of thin, branching bony plates called trabeculae. The spaces between the trabeculae are filled with bone marrow. Spongy bone helps reduce the weight of the bone while providing support and flexibility.
Bone Marrow: Within the spaces of spongy bone is bone marrow. There are two types of bone marrow: red marrow and yellow marrow. Red marrow is responsible for producing blood cells, including red blood cells, white blood cells, and platelets. Yellow marrow consists mainly of fat cells and serves as a storage site for adipose tissue.
Articular Cartilage: At the ends of long bones, where they articulate with other bones in joints, there is a layer of smooth, slippery cartilage called articular cartilage. It helps reduce friction and absorbs shock during movement, facilitating smooth joint motion.
Medullary Cavity: Within the diaphysis or shaft of the long bone, there is a hollow space called the medullary cavity. The medullary cavity contains bone marrow and serves as a storage site for yellow marrow.