Human Skeletal system details
The human skeletal system
Is composed of bones, cartilage, and ligaments. It provides support and structure to the body, as well as protection for vital organs and tissues.
There are 206 bones
The adult, human body, is divided into two main categories: the axial skeleton and the appendicular skeleton.
The axial skeleton includes the skull, vertebral column, and rib cage. The skull protects the brain and supports the face. The vertebral column, or spine, consists of 33 vertebrae that provide support for the body and protect the spinal cord. The rib cage includes 12 pairs of ribs that protect the heart and lungs.
The appendicular skeleton includes the bones of the arms, legs, shoulders, and hips. The upper limb consists of the humerus, radius, ulna, carpals, metacarpals, and phalanges. The lower limb consists of the femur, tibia, fibula, tarsals, metatarsals, and phalanges. The shoulders are composed of the clavicle and scapula, while the hips consist of the pelvic girdle, which includes the ilium, ischium, and pubis.
Cartilage is a connective tissue that provides cushioning and flexibility to the joints. It is found at the ends of bones and in other areas where bones meet, such as in the nose and ears.
Ligaments are strong bands of connective tissue that connect bones to each other and provide stability to joints.
In addition to providing support and protection, the skeletal system also plays a role in the production of blood cells, the storage of minerals such as calcium and phosphorus, and the facilitation of movement through muscle attachment points.
Bone
Bone is a living tissue that undergoes constant remodeling throughout life. Bone cells called osteoclasts break down old bone tissue, while other cells called osteoblasts build new bone tissue. This process helps maintain bone strength and integrity.
Bones are classified by their shape: long bones (such as the femur and humerus), short bones (such as the carpals in the wrist), flat bones (such as the skull bones), and irregular bones (such as the vertebrae).
Bones are made up of a hard outer layer called compact bone, which is dense and strong, and a spongy inner layer called cancellous bone, which is lighter and more porous. The spaces within cancellous bone are filled with bone marrow, which is responsible for producing blood cells.
Joints are the places where two or more bones meet. There are several types of joints, including hinge joints (such as the knee), ball-and-socket joints (such as the hip), and pivot joints (such as the joint between the radius and ulna in the forearm).
Some bones are fused together in adults. For example, the skull bones are fused to protect the brain, and the sacrum and coccyx (at the base of the spine) are fused to provide stability to the pelvis.
Bones are susceptible to a variety of diseases and conditions, including fractures, osteoporosis (a condition characterized by loss of bone density), and arthritis (inflammation of the joints).
Proper nutrition, exercise, and adequate intake of calcium and vitamin D are important for maintaining strong bones and preventing bone-related diseases.
