Zusammenfassung der Ressource
muscle tissue
- muscle tissue — specialized for contraction, produces movement muscle cells have organelles and
properties distinct from those of other cells
- Skeletal Muscle Tissue — organ of muscular
system contains large muscle cells (1ft)
individual muscle cells called muscle fibers
— bc they are long and slender each muscle
fiber has 100s of nuclei inside plasma
membrane — the fibers are described as
multinucleate muscle fibers here, incapable
of dividing new fibers produced via division
of myosatellite cells — stem cells in adult
skeletal tissue — capable of repairing itself
after injury do not usually contact unless
stimulated by nerves nervous system
provides voluntary control over skeletal
muscle activities — skeletal muscle called
striated voluntary muscle muscle fibers tied
together by collagen and elastic fibers
- Cardiac Muscle Tissue found in heart
cardiocyte — heart cell, smaller than
skeletal muscle cell, has one nucleus
but some have 5 straight striations bc
of the myosin and actin filaments
cardiac muscle tissues consists of
branching network of interconnected
cardiac muscle cells — cells are
connected as regions called
intercalated discs membranes locked
together by desmosomes,
proteoglycans (lock cells together),
gap junctions (help ion movement
that helps to synchronize muscle
contractions) limited ability to repair
itself — incomplete repairs — heart
function lost pacemaker cells set
regular heart rate cardiac muscle
called striated involuntary muscle bc
there is no voluntary control over
cells
- Smooth muscle tissue found in walls of blood vessels,
around hollow organs like urinary bladder, and in layers
around respiratory, cardiovascular, digestive,
reproductive tracts smooth muscle cells small,
spindle-shaped, w/ tapering edges and single, oval
nucleus cells can divide — regenerate after injury actin
and myosin filaments arranged differently — no striations
contract on their own, gap junctions coordinate cell
movement some cell contractions can be controlled by
nervous system smooth muscles known as nonstriated
involuntary muscle