Muscles pull on the joints, allowing us to move. Muscles make up half of a person's body weight. They are connected to bones by tough, cord-like tissues called tendons, which allow the muscles to pull on bones. What is bone made up of? Made mostly of collagen, bone is living, growing tissue.
Collagen is a protein that provides a soft framework, and calcium phosphate is a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bone strong and flexible enough to withstand stress. What bones can you live without? You can still have a fairly normal life without one of your lungs, a kidney, your spleen, appendix, gall bladder, adenoids, tonsils, plus some of your lymph nodes, the fibula bones from each leg and six of your ribs.
Why are bones important to the body? Bones play an important part in the overall function of your body. They provide a frame for your body, they protect vital organs such as your heart, and they even produce blood that is used by your body. When you walk or run, it is because your bones and muscles are working together. What is long bone in human body? A long bone is one that is cylindrical in shape, being longer than it is wide.
Long bones are found in the arms humerus, ulna, radius and legs femur, tibia, fibula , as well as in the fingers metacarpals, phalanges and toes metatarsals, phalanges. Long bones function as levers; they move when muscles contract. How do your bones grow?
As you grow, the cartilage in your bones grows. The quadriceps femoris is a group of muscles located in the front of the thigh. The Latin translation of 'quadriceps' is 'four headed,' as the group…. The palmaris brevis muscle lies just underneath the skin. It is a short muscle on the flat of the hand. The muscle begins at the flexor retinaculum in….
The movement of the upper arm and shoulder is controlled by a group of four muscles that make up the rotator cuff. The largest and strongest muscle in…. The extensor pollicis longus muscle begins at the ulna and the interosseous membrane, a tough fibrous tissue that connects the ulna and the radius in….
The biceps brachii, sometimes known simply as the biceps, is a skeletal muscle that is involved in the movement of the elbow and shoulder.
It is a…. The skeletal system is the foundation of your body, giving it structure and allowing for movement. Health Conditions Discover Plan Connect. Read this next. Supraspinatus Medically reviewed by the Healthline Medical Network. Quadratus plantae Medically reviewed by the Healthline Medical Network.
Depressor labii inferioris Medically reviewed by the Healthline Medical Network. Quadriceps femoris Medically reviewed by the Healthline Medical Network. Bones are fastened to other bones by long, fibrous straps called ligaments LIG-uh-mentz. Cartilage KAR-tul-ij , a flexible, rubbery substance in our joints, supports bones and protects them where they rub against each other.
The bones of kids and young teens are smaller than those of adults and contain "growing zones" called growth plates. These plates consist of multiplying cartilage cells that grow in length, and then change into hard, mineralized bone.
These growth plates are easy to spot on an X-ray. Because girls mature at an earlier age than boys, their growth plates change into hard bone at an earlier age.
Bone-building continues throughout life, as a body constantly renews and reshapes the bones' living tissue. Bone contains three types of cells:. Muscles pull on the joints, allowing us to move.
They also help the body do such things as chewing food and then moving it through the digestive system. Even when we sit perfectly still, muscles throughout the body are constantly moving.
Muscles help the heart beat, the chest rise and fall during breathing, and blood vessels regulate the pressure and flow of blood. When we smile and talk, muscles help us communicate, and when we exercise, they help us stay physically fit and healthy. The movements that muscles make are coordinated and controlled by the brain and nervous system.
The involuntary muscles are controlled by structures deep within the brain and the upper part of the spinal cord called the brain stem.
The voluntary muscles are regulated by the parts of the brain known as the cerebral motor cortex and the cerebellum ser-uh-BEL-um. When you decide to move, the motor cortex sends an electrical signal through the spinal cord and peripheral nerves to the muscles, making them contract.
The motor cortex on the right side of the brain controls the muscles on the left side of the body and vice versa. The cerebellum coordinates the muscle movements ordered by the motor cortex.
Sensors in the muscles and joints send messages back through peripheral nerves to tell the cerebellum and other parts of the brain where and how the arm or leg is moving and what position it's in.
This feedback results in smooth, coordinated motion. If you want to lift your arm, your brain sends a message to the muscles in your arm and you move it.
When you run, the messages to the brain are more involved, because many muscles have to work in rhythm. Muscles move body parts by contracting and then relaxing.
Muscles can pull bones, but they can't push them back to the original position. So they work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint. Then, when the movement is completed, the flexor relaxes and the extensor contracts to extend or straighten the limb at the same joint.
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