Flashcards in ch 10 test Deck (43)
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1
list the functions of muscle tissue
1. produce skeletal movement 2. maintain posture and body position 3. support soft tissues 4. guard entrances and exits 5. maintain body temperature 6. store nutrient reserves
2
epimysium
exterior collagen layer that is connected to deep fascia and seperates muscle from surrounding tissues
3
perimysium
surrounds muscle fiber bundles (fascicles) and contains the blood vessel and nerve supply to fascicles
4
endomysium
surrounds individual muscle cells, contains capillaries and nerve fibers contacting muscle cells as well as myosatellite cells (stem cells) that repair damage
5
fascicle
muscle fiber bundles
6
sarcolemma
the cell membrane of muscle cell that surrounds the sarcoplasm. A change in transmembrane potential begins contractions.
7
transverse tubules
transmit action potential through cell wh allows entire muscle fiber to contract simultaneously
8
triad
formed by 1 T tubule and 2 terminal cisternae
9
cisternae
concentrate calcium then release into sarcomeres to begin muscle contraction
10
myofibrils
lengthwise subdivisions w/n muscle fiber made up of myofilaments
11
myofilaments
bundles of protein filaments responsible for muscle contraction (thick and thin)
12
Thin filaments
made up of F-actin and nebulin with troponin and tropomyosin
13
actin
2 twisted rows of globular G-actin which have the active sites that bind w myosin
14
tropomyosin
a double strand that prevents actin-myosin interaction
15
troponin
a globular protein that binds tropomyosin to G-actin and is controlled by calcium
16
thick filament
contain myosin subunits and titin strands that recoil after stretching
17
myosin
tail- binds to other myosin molecules
head- made of 2 globular protein subunits that reach for nearest thin filament forming cross bridges
18
sarcomeres
contractile unit of muscles that form visable patterns within myofibrils (stripes)
19
z-line
center of I band at the 2 ends of sarcomeres
20
m-line
the center of the A band at the midline of sarcomere
21
zone of overlap
where thick and thin filaments overlap
22
titin
strands of protein that reach from tips of thick filaments to the z-line and stabilize the filaments
23
sliding filament theory
thin filaments of sarcomere slide toward the m-line alongside thick filaments; width of A zone stays the same while Z lines move closer together
24
neuromuscular junction
special intercellular connectin between the nervous system and skeletal muscle fiber that controls calcium ion release into the sarcoplasm
25
stimulation sequence
1. stim from nerve 2. Ach released 3. binds to sites on muscle 4. action potential created by change in membrane voltage 5. all or nothing principle 6. sodium fromoutside muscle cell enters
26
the contraction cycle
1. contraction cycle begins 2. active site exposure 3. cross-bridge formation 4. myosin head pivoting 5. cross bridge detachment 6. myosin reactivation
27
roll of acteylcholine
neurotransmitter that changes the permeability to sodium ions
28
roll of sodium
creates the action potential in the sarcolemma
29
roll of calcium
binds w troponin to rotate tropomyosin and expose actin to myosin
30
