Musculoskeletal System 

Spine

The spine is one of the most important bones in the body. It provides support as the structural framework as well as protection. The spine incases the spinal cord which is critical to the central nervous system transmitting signals to the rest of the body. The spine acts as a shock absorbed with discs that reduce the impact and pressure on the vertebrae. Finally, regulating involuntary functions such as breathing, heart rate, and digestion is through the spine. 

Bones

Bones come in all shapes and sizes including long bones, short bones, flat, and irregular shapes as well. They are built in levers that support the body maintaining its upright structure. In addition, bones can protect organs such as the ribcage protecting the heart and lungs and the skull protecting the brain. There are 206 bones in an adult human, but children are born with 270. Some bones in children end up fusing as they grow older. In addition to support and protection bones also: 

• Store minerals like calcium and phosphorus

• Produce blood cells from bone marrow

• Store fat

• Release hormones

Tendons and Ligaments

Tendons are tissues that connect the muscle to the bones. In addition, ligaments connect bones to other bones. Tendons and ligaments are made of collagen fibers. Tendons, however, are less elastic due to its parallel and dense structure. Ligaments are more elastic and able to stretch.

Joints

Joints are where two bones meet. Most joints utilize cartilage for cushioning and support to reduce friction and damage between bones. However, other forms of joints such as synovial and fibrous joints have other methods to reduce friction. Synovial joints have synovial fluid to lubricate the joint and reduce friction. Fibrous joints are connected by fibrous connective tissue which allows for slight movement.