The Musculoskeletal System
The musculoskeletal system is made up of all of the bones in your body and the muscles that make them move.
The musculoskeletal system is made up of all of the bones in your body and the muscles that make them move.
Structural Features
The skeleton consists of three different types of connective tissue: bones, ligaments, and cartilage. Bone tissue is hard and dense. It consists of bone cells within a matrix of minerals (mainly calcium and phosphorus) and collagen fibres. Canals inside the bones contain nerves and blood vessels (Figure 2). Only a small percentage of bone tissue is actually living.
The skeleton consists of three different types of connective tissue: bones, ligaments, and cartilage. Bone tissue is hard and dense. It consists of bone cells within a matrix of minerals (mainly calcium and phosphorus) and collagen fibres. Canals inside the bones contain nerves and blood vessels (Figure 2). Only a small percentage of bone tissue is actually living.
Ligaments are tough, elastic connective tissues that hold bones together at the joints. They are made up mostly of long fibres of collagen. Cartilage is a dense connective tissue found in the ear, nose, esophagus, the disks between our vertebrae, and joints (Figure 3). Cartilage is made up of special cells in a matrix of collagen fibres. It provides a strong, flexible, low-friction support for bones and other tissues.
The other part of the musculoskeletal system is the muscle. Muscle tissue consists of bundles of long cells called muscle fibres that contain specialized proteins. These proteins cause the muscle to contract when signalled by nerve cells. When they contract, the muscles get shorter and thicker. Skeletal (voluntary) muscle tissue is one of the three types of muscle tissue. The others are smooth (involuntary) muscle, mostly located in the intestines,
and cardiac muscle in the heart. Skeletal muscle is attached to bones by tendons, allowing the movement of body parts (Figure 4).
and cardiac muscle in the heart. Skeletal muscle is attached to bones by tendons, allowing the movement of body parts (Figure 4).
Support, Protection, and Movement The main role of the skeleton is to provide structure and support for our bodies and anchor points for our muscles. Some bones also protect the soft internal organs and the brain. Bones also store calcium and other minerals needed by the organism, and some bones contain marrow, which produces red and white blood cells. Cartilage provides a smooth surface where bones come together at a joint, preventing damage to the ends of the bones. We use skeletal muscle for voluntary movements of the body, such as walking, running, and body movement.
How Muscles Make Bones Move
Each end of a skeletal muscle is connected by tendons to one or more different bones in the skeleton. Tendons are similar to ligaments but are less elastic and connect
muscles to bones. When muscles contract in response to signals from
the nervous system, they exert a force. This force moves one or both of the bones to which the muscle is connected. Muscles can pull, but they cannot push, so skeletal muscles always work in opposing pairs or groups(Figure 5).
Each end of a skeletal muscle is connected by tendons to one or more different bones in the skeleton. Tendons are similar to ligaments but are less elastic and connect
muscles to bones. When muscles contract in response to signals from
the nervous system, they exert a force. This force moves one or both of the bones to which the muscle is connected. Muscles can pull, but they cannot push, so skeletal muscles always work in opposing pairs or groups(Figure 5).
Problems with the Musculoskeletal System
The musculoskeletal system, like other systems, is susceptible to diseases. Osteoporosis is a disease that can affect people of all ages but is a more common problem among older women. This disease involves loss of bone tissue, making the bones brittle and weak (Figure 6). Osteoporosis does not cause any pain, so only a bone density test can indicate the presence of the disease. It is linked to a loss of calcium in the bones, so women are encouraged to consume foods or supplements containing calcium and vitamin D. Physical
exercise can also help increase bone mass and lessen the risks of osteoporosis. Because of its role in support and protection, the musculoskeletal system experiences physical impacts and stresses. Extreme movements can tear ligaments, tendons, and muscle tissues; severe impacts can fracture bones. After a serious injury, X-rays are taken to determine if a bone is fractured and how the injury should be treated.
The musculoskeletal system, like other systems, is susceptible to diseases. Osteoporosis is a disease that can affect people of all ages but is a more common problem among older women. This disease involves loss of bone tissue, making the bones brittle and weak (Figure 6). Osteoporosis does not cause any pain, so only a bone density test can indicate the presence of the disease. It is linked to a loss of calcium in the bones, so women are encouraged to consume foods or supplements containing calcium and vitamin D. Physical
exercise can also help increase bone mass and lessen the risks of osteoporosis. Because of its role in support and protection, the musculoskeletal system experiences physical impacts and stresses. Extreme movements can tear ligaments, tendons, and muscle tissues; severe impacts can fracture bones. After a serious injury, X-rays are taken to determine if a bone is fractured and how the injury should be treated.