Muscular Tissue Flashcards
what are the three muscular tissues
- skeletal (voluntary)
- smooth (involuntary)
- cardiac(involuntary)
what is a myoglobin
muscle protein that carries oxygen
what is a myofilament
protein fiber in muscle cell
what is a myosin
specific muscle protein
what is the sarcoplasm
cytoplasm for muscle cell
what is reference point for muscular tissue
skeletal muscle
what is name of muscle cell
myofiber
what is the sarcolemma
cell membrane of muscle cell
what are general characteristics of muscle tissue
contains: myofibers, sarcolemma, sarcoplasm (has all normal organelles), sarcoplasmic reticulum, myofilaments
what are to the two types of myofilaments
actin-thin filament
myosin-thick filament
what are the mechanisms of muscle contraction
- nerve impulse reaches muscle.
- Signal is transmitted to the sarcolemma of the Myofiber.
- Chemical signal causes Ca2+ stored in the sarcoplasmic reticulum to be released.
- Ca2+ ions enter the Myofiber’s sarcoplasm.
- Increased Ca2+ ions activates bridge between Actin & Myosin.
- Actin can now slide (be pulled) over the Myosin.
what is the basic unit of myofiber
sarcomere
what are characteristics of skeletal muscle tissue
- visible striations bc of high number of actin & myosin in parallel formation,
- under voluntary control of brain,
- multi-nucleated,
- all myofibers must have nerve connection to contract,
what is atrophy
the degeneration or wasting away of muscle cells
what is hypertrophy
enlargement due to increase in size of muscle cells
what is hyperplasia
enlargement due to increase in number of muscle cell
what are the types of muscular activity
- single event
- repetitive
what are characteristics of smooth muscle tissue
- has actin & myosin.
- spindle shaped cells.
- one centrally located nucleus per cell.
- grouped in small clusters.
- separated by fine collagen & reticular CT.
- can stretch & maintain tension.
- under involuntary control.
- must have a nerve connection to contract.
what is a gap junction
a specialized communication area between the cells
what are characteristics of cardiac muscle
- found only in heart.
- has visible striations, simular to skeletal muscle.
- have intercalated disc.
- under involuntary control.
- self-activated contractions.
what is an intercalated disc
cardiac tissue’s gap junction that allows signal for a contraction to pass from cell to cell without nerve connection
