Lecture 6: Muscle Introduction Flashcards
What are the characteristics of muscle cells
IRRITABILITY (“Electrical Excitability”)
• CONTRACTILITY
• EXTENSIBILITY
• ELASTICITY
what are the 3 types of msucle cells
skeletal
smooth
cariac
what are the chracteritics of skeletal muscle
striated
voluntary
what are the chracteristics of smooth msucle
non striated, non voluntary, visceral
what are the chracteritics of cardiac muscles
striated
non voluntary
specialized
what is fascia
Dense irregular connective tissue • Completely surrounds the muscle • Surrounds groups of muscles • Skeletal muscle found deep to it • Extensions of the fascia = Epimysium
What is the whole muscle covered by?
EPIMYSIUM
what is the whole msucle a group of
FASICLES
What is each fasicle covered by
perimysium
what is each fasicle made up of?
made up of bundles of MUSCLE
FIBERS
what is each muscle fiber covered with
endomysium
what is another name for muscle fiber?
muscle cell
be able to label the msucle diagram
./
Deep to the endomysium, what is each msucle fiber covered with
sarcolemma
what is each individual myofibril covered with>?
SR
what is each msucle fiber made up of?
bundles of myofibrils
what is Each MYOFIBRIL made up of
MYOFILAMENTS
proteins
within each sarcomere, what does each myofibril contain
3000 ACTIN (thin) myofilaments* 1500 MYOSIN (thick) myofilaments*
What do the actin and mysosin filaments die
Glide between each other in the contraction/relaxation of
muscle (length of each does not change, but the amount of
overlap does)
what is the sarcomere
fucntional unit of a myofibril
be able to label the actin and myosin filamets
/
What are the cross striations of the sarcomere
alternating bands of light and dark
what are the dark bands made up of/ the light bands (in a darcomere)
Dark Bands (A Bands): Actin + Myosin • Light Bands (I Bands): Actin only
true or false: H zone is only myosin?
truw
What are the z lines and m lines
Z lines (disks): indicate boundaries of sarcomere
M line (protein bands): center of sarcomere