ch 10 test

Question 1

list the functions of muscle tissue

Answer 1

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

Question 2

epimysium

Answer 2

exterior collagen layer that is connected to deep fascia and seperates muscle from surrounding tissues

Question 3

perimysium

Answer 3

surrounds muscle fiber bundles (fascicles) and contains the blood vessel and nerve supply to fascicles

Question 4

endomysium

Answer 4

surrounds individual muscle cells, contains capillaries and nerve fibers contacting muscle cells as well as myosatellite cells (stem cells) that repair damage

Question 5

fascicle

Answer 5

muscle fiber bundles

Question 6

sarcolemma

Answer 6

the cell membrane of muscle cell that surrounds the sarcoplasm. A change in transmembrane potential begins contractions.

Question 7

transverse tubules

Answer 7

transmit action potential through cell wh allows entire muscle fiber to contract simultaneously

Question 8

triad

Answer 8

formed by 1 T tubule and 2 terminal cisternae

Question 9

cisternae

Answer 9

concentrate calcium then release into sarcomeres to begin muscle contraction

Question 10

myofibrils

Answer 10

lengthwise subdivisions w/n muscle fiber made up of myofilaments

Question 11

myofilaments

Answer 11

bundles of protein filaments responsible for muscle contraction (thick and thin)

Question 12

Thin filaments

Answer 12

made up of F-actin and nebulin with troponin and tropomyosin

Question 13

actin

Answer 13

2 twisted rows of globular G-actin which have the active sites that bind w myosin

Question 14

tropomyosin

Answer 14

a double strand that prevents actin-myosin interaction

Question 15

troponin

Answer 15

a globular protein that binds tropomyosin to G-actin and is controlled by calcium

Question 16

thick filament

Answer 16

contain myosin subunits and titin strands that recoil after stretching

Question 17

myosin

Answer 17

tail- binds to other myosin molecules

head- made of 2 globular protein subunits that reach for nearest thin filament forming cross bridges

Question 18

sarcomeres

Answer 18

contractile unit of muscles that form visable patterns within myofibrils (stripes)

Question 19

z-line

Answer 19

center of I band at the 2 ends of sarcomeres

Question 20

m-line

Answer 20

the center of the A band at the midline of sarcomere

Question 21

zone of overlap

Answer 21

where thick and thin filaments overlap

Question 22

titin

Answer 22

strands of protein that reach from tips of thick filaments to the z-line and stabilize the filaments

Question 23

sliding filament theory

Answer 23

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

Question 24

neuromuscular junction

Answer 24

special intercellular connectin between the nervous system and skeletal muscle fiber that controls calcium ion release into the sarcoplasm

Question 25

stimulation sequence

Answer 25

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

Question 26

the contraction cycle

Answer 26

1. contraction cycle begins 2. active site exposure 3. cross-bridge formation 4. myosin head pivoting 5. cross bridge detachment 6. myosin reactivation

Question 27

roll of acteylcholine

Answer 27

neurotransmitter that changes the permeability to sodium ions

Question 28

roll of sodium

Answer 28

creates the action potential in the sarcolemma

Question 29

roll of calcium

Answer 29

binds w troponin to rotate tropomyosin and expose actin to myosin

Question 30

roll of ATP

Answer 30

breakdown creates energy

Question 31

twitch

Answer 31

latent period followed by contraction phase then relaxation phase

Question 32

treppe

Answer 32

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

Question 33

wave summation

Answer 33

successive stimuli arrive before the relaxation phase has been completed

Question 34

incomplete tetanus

Answer 34

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

Question 35

complete tetanus

Answer 35

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

Question 36

isotonic contraction

Answer 36

skeletal muscle changes length resulting in motion

Question 37

concentric contraction

Answer 37

isotonic contraction when the muscle shortens

tension>load (resistance)

Question 38

eccentric contraction

Answer 38

isotonic contraction when muscles lengthen

tension<load

Question 39

isometric contraction

Answer 39

skeletal muscle develops tension but is prevented from changing legnth

Question 40

ATP energy

Answer 40

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

Question 41

creatine phosphate

Answer 41

the storage molecule for excess ATP energy in resting muscles

Question 42

glycolysis

Answer 42

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

Question 43

aerobic metabolism

Answer 43

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