#Lumen learning biology skin
In contrast, smooth muscle occurs at various scales in almost every organ, from the skin (in which it controls erection of body hair) to the blood vessels and digestive tract (in which it controls the caliber of a lumen and peristalsis, respectively). It is connected by tendons to processes of the skeleton. Skeletal muscle, which involves muscles from the skeletal tissue, is arranged in discrete groups (Figure 1). Muscle spindles are distributed throughout the muscles, and provide sensory feedback information to the central nervous system. These bundles are then grouped together to form muscle, and is lined by epimysium. Muscle cells are bound together by perimysium into bundles called fascicles. Individual muscle cells are lined with endomysium. Within the cells are myofibrils myofibrils contain sarcomeres which are composed of actin and myosin. Muscle is composed of muscle cells (sometimes known as “muscle fibers”). Voluntary muscle contraction is used to move the body and can be finely controlled, such as movements of the finger or gross movements like those of the biceps and triceps. Much of muscle contraction occurs without conscious thought and is necessary for survival, like the contraction of the heart or peristalsis, which pushes food through the digestive system. Its function is to produce force and cause motion, either locomotion or movement within internal organs. Muscle is contractile tissue and is derived from the mesodermal layer of embryonic germ cells.
The muscular system, in vertebrates, is controlled through the nervous system, although some muscles, like cardiac muscle, can be completely autonomous. The muscular system is the biological system of humans that produces movement.
0 kommentar(er)
