Muscles: movement, protection, stability and maintaining body temperature
Despite the different functions of muscles, all have cells that contract.
Muscle is made up of small tissue thst can contract in an orderly way. When muscles contract, cells become shorter.
MOVEMENT
Many muscles are attached to bone and enable your skeleton to move. Bones move when the muscles contract. This movement may be fast or slow (run or walk)
Many muscles are not attached to bone. The contractions in these muscles cause blood and food through out your body. Peristalsis. They cause your heart to beat.
TYPES OF MUSCLE
Heart is made up of cardiac muscle. It is involuntary-you can’tcontrol.Cardiac muscle cells have disks at the end of the cells which send messages to other cardiac cells which signals to other cardiac cells to contract. Modulated by neural activity and some hormones. SA node.
Smooth Muscle are involuntary muscles named for their smooth appearance. Blood vessels and many organs such as the stomach are lined with smooth muscle. controlled by the autonomic nervous system; may either be generally inactive and then respond to neural stimulation or hormones or may be rhythmic
Skeletal muscle-move us around and responsible for most of our behavior; most attached to bones at each end via tendons.
flexion - contraction of flexor muscles, drawing in of a limb
extension - opposite of flexion, produced by contraction of extensor muscles (antigravity)
Flexion is a motion in which the angle of the joint involved decreases, as in bending the elbow so that the forearm is brought toward the upper arm. Extension is a movement that increases the angle of the joint, as in straightening the elbow.
Flexion of the biceps and extension of the triceps
Reflex- stimulating patellar tendon causes knee to kick
HEALTHY MUSCLES
Muscles need energy to perform. Eating a diet full of nutrients such as protein, fiber and potassium can help keep muscles strong. Exercise is very important. Muscle cells decrease in size and strength without exercise. Decreased muscle strength increase the risk for heart disease and bone injuries as well as joints less stable.
HOMEOSTASIS
Muscles contractions convert chemical energy to thermal energy to keep you warm. When you exercise, your cells need more oxygen and release more waste such as CO2. Cardiac muscles contract more often to supply more oxygen and remove more waste circulating blood faster through out the body.
Tendons attach muscles to bone