One of the contractie proteins in muscle tissue. forms the thick filaments. has intrinsic ATPase activity and can exist in two conformations, either high energy or low energy.
A contractile protein. In skeletal and cardiac muscle, it polymerizes (along with other proteins) to form the thin filaments. involved in many contractile activities, such as cyotkinesis, pseudopod formation, and muscle contraction.
a type of non-striated muscle, found within the bladder, abdominal cavity, the uterus, male and female reproductive tracts, the gastrointestinal tract and elsewhere. mainly involuntary, innervated by autonomic nervous system. mononucleate. contain thick and thin filaments that are not organized into sarcomeres. contain intermediate filaments which are attached to dense bodies.
striated (composed of sarcomeres). mononucleate. each cell is separated by an intercalated disc that contains gap junctions. The mitochondria are larger and more numerous. not connected to bone.
a type of striated muscle, usually attached to the skeleton.
the smallest functional unit of skeletal muscle. composed of many strands of thick and thin filaments laid side by side to form a cylindrical segment. they are positioned end to end to form a myofibril.
displaced from its normal binding groove by troponin as part of the regulation of muscle contraction
secrete collagen and organic compounds upon which bone is formed, incapable of mitosis, differentiate into osteocytes.
reabsorb bone matrix, releasing minerals back into the blood. believed to develop from monocytes.
flexible, resilient connective tissue. composed primarily of collagen, has great tensile strength. contains no blood vessels or nerves.
a tough band of fibrous connective tissue that connects muscle to bone and is built to withstand tension.
a special type of smooth endoplasmic reticulum found in smooth and striated muscle. lumen is filled with Ca2+ ions
the modified cell membrane of a muscle cell.
a deep invagination of the plasma membrane found in skeletal and cardiac muscle cells which allows depolarization of the membrane to quickly penetrate to the interior of the cell. allows for a uniform contraction of the muscle.
The division between neighboring cardiac muscle cells. include gap junctions, which allow the cells to function as a unit.
incapable of mitosis, exchange nutrients and waste materials with the blood.
the main or mid section shaft of a long bone.
a series of tubes burrowed by osteoclasts around narrow channels formed by lamellae in compact bone. contain blood and lymph vessels, and are connected by Volkmann's canals.
growth plate, the cartilage plate in the long bones of children and adolescents.
muscle responsible for the movement
assist the agonist by stabilizing the origin bone or by positioning the insertion bone during the movement
connects bone to bone
made of several myosin molecules wrapping around each other
composed mainly of actin. attached to the actin are troponin and tropomyosin
The band of the sarcomere that extends the full length of the thick filament. includes regions of thick and thin filament overlap, as well as a region of thick filament only. does not shorten during muscle contraction.
The region of the sarcomere made up only of thin filaments. is bisected by a Z line. get shorter (and may disappear completely) during muscle contraction.
single-unit smooth muscle
also called visceral, most common. cells connected by gap junctions spreading the action potential from a single neuron through a large group of cells, and allowing the cells to contract as a single unit. found in small arteries and veins, the stomach, intestines, uterus, and urinary bladder.
multiunit smooth muscle
attached directly to a neuron. a group can contract independently of other muscle fibers in the same location. found in the large arteries, bronchioles, pili muscles attached to hair follicles, and the iris.
differentiate into osteoblasts
contains red bone marrow, the site of red blood cell development
surrounds the medullary cavity which holds yellow bone marrow, which contains adipose cells for fat storage. highly organized.
osteocytes trapped between the lamellae exchange nutrients via these
reduces friction and absorbs shock in joints
A lubricating, nourishing fluid found in joint capsules. contains phagocytic cells