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Flashcards in ch 10 test Deck (43):
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

roll of ATP

breakdown creates energy

31

twitch

latent period followed by contraction phase then relaxation phase

32

treppe

increase in peak tension w ea successive stim delivered shortly after the completion of the relaxation phase of the preceding twitch

33

wave summation

successive stimuli arrive before the relaxation phase has been completed

34

incomplete tetanus

occurs if the stim frequency increases further, tension production rises to a peak and periods of relaxation are very brief

35

complete tetanus

stim frequency is so high that the relaxation phase is eliminated, tension plateaus at maximum levels

36

isotonic contraction

skeletal muscle changes length resulting in motion

37

concentric contraction

isotonic contraction when the muscle shortens
tension>load (resistance)

38

eccentric contraction

isotonic contraction when muscles lengthen
tension

39

isometric contraction

skeletal muscle develops tension but is prevented from changing legnth

40

ATP energy

muscles store enough to start contraction then must create more as needed- aerobic metabolism of fatty acids in the mitochondria and/or anaerobic glycolysis in the cytoplasm

41

creatine phosphate

the storage molecule for excess ATP energy in resting muscles

42

glycolysis

primary energy source for peak muscular act.that produces 2 ATP per molecule of glucose an breaks down glocose from glycogen stored in skeletal muscles

43

aerobic metabolism

primary energy source for resting muscles, breaks down fatty acids, produces 34 ATP molecules per glucose molecules