The Muscular system Flashcards
what are the characteristics of smooth muscle
involuntary
lacks striations
spindle-shaped cells
single nucleus
found mainly in the walls of hollow organs eg urinary bladder, respiratory passages and stomach
smooth muscle propels substances along pathways
smooth muscle contraction is slow and sustained.
what are the characteristics of skeletal muscle
voluntary
multinucleate cells
they are attached to the skeleton via tendons
skeletal muscles can be activated by reflexes
skeletal muscle fibers are soft and fragile
what are the characteristics of cardiac muscle
involuntary
only found in the heart
striated
cardiac muscle fibers are branching cells joined by special gap junctions called intercalated discs
what is the function of the endomysium
the sheet of connective tissue that each muscle fiber/cell is wrapped around
what is the function of the perimysium
a coarser fibrous membrane wrapped around several muscle fibres, which bundle to form a fascicle.
what is the function of the epimysium
layer of collagen fibres that surrounds the muscle. It is a layer which covers the entire muscle. At the end of the epimysium, that extend beyond the muscle blend into either into a strong cordlike tendon or a sheetlike aponeurosis, which indirectly attaches muscle to bone
what is the function of the endomysium
what is a fascicle
a bundle of nerve or muscle fibres bound together by connective tissue.
(the perimysium)
what is the function of tendons
Providing durability and conserving space.
Anchors muscles to bones
what is the sarcolemma
the sarcolemma is the plasma membrane of a muscle fiber. it surrounds the sarcoplasm (cytoplasm of a muscle fiber). a sudden change in membrane potential initiates a contraction.
