Muscular System

Question 1

Continuous with tendon which is attached to bone

Answer 1

Epimysium

Question 2

Origin

Answer 2

Proximal attachment

Question 3

Insertion

Answer 3

Distal attachment

Question 4

Bundles of muscle fibers

Answer 4

Fasiculi

Question 5

Connective tissue around fasiculi

Answer 5

Perimysium

Question 6

Connective tissue around each fiber. Continuous with sarcolemma

Answer 6

Endomysium

Question 7

Junction between motor neuron and muscle fibers it innervates

Answer 7

NMJ

Question 8

Each cell has this many NMJ, but

Answer 8

One, single motor neuron can innervate many fibers

Question 9

Motor neuron and fibers it innervates

Answer 9

Motor unit

Question 10

Contains contractile components, glycogen, fat, enzymes, mitochondria, SR

Answer 10

Sarcoplasm

Question 11

Contain contractile Apparatus

Answer 11

Myofibrils

Question 12

Thick, has cross bridges

Answer 12

Myosin

Question 13

Thin, two strands in double helix

Answer 13

Actin

Question 14

Smallest contractile unit of skmm

Answer 14

Sarcomere

Question 15

CENTER of sarcomere. Myosin anchor

Answer 15

m bridge

Question 16

ENDS of sarcomere. Actin anchor

Answer 16

z line

Question 17

DARK. alignment of myosin

Answer 17

a band

Question 18

LIGHT. Only actin. Z line in middle

Answer 18

I band

Question 19

CENTER. M bridge in middle, only myosin

Answer 19

H zone

Question 20

These decrease during contraction…

Answer 20

H zone and I band

Question 21

Intricate system of tubules parallel to each myofibril

Answer 21

Sarcoplasmic reticulum

Question 22

SR terminates as…

Answer 22

Vesicles near z lines

Question 23

Calcium stored in…

Answer 23

Vesicles of SR

Question 24

In SR, this controls contraction…

Answer 24

Regulation of calcium

Question 25

Run perpendicular to SR and terminate near z lines between two vesicles

Answer 25

T tubules

Question 26

T tubules are continuous with...

Answer 26

Sarcolemma at surface

Question 27

Discharge of AP arrives nearly...

Answer 27

Simultaneously from surface to all depths

Question 28

States that actin slide inward on myosin, pulling z lines to center

Answer 28

Sliding filament theory

Question 29

Causes movement during SFT

Answer 29

Flexion of cross bridges on actin

Question 30

How must flexions occur

Answer 30

Very rapid and repeated

Question 31

Phases of SFT. 5

Answer 31

Resting, excitation contraction coupling, contraction,recharge, relaxation

Question 32

Little Calcium present, few bound cross bridges, no tension

Answer 32

Resting

Question 33

SR stimulated to release calcium during

Answer 33

Excitation contraction coupling

Question 34

Calcium binds with

Answer 34

Troponin

Question 35

During contraction, energy comes from

Answer 35

Hydrolysis of ATP to ADP

Question 36

Another ATP must replace ADP in order...

Answer 36

For cross bridge head to detach and recock

Question 37

If calcium is present..

Answer 37

Continuation of contraction. Relaxation if not present

Question 38

Recharge continues as long as there is...

Answer 38

Calcium, ATP, and myosin ATPase

Question 39

Relaxation occurs when...

Answer 39

Motor nerve isn't stimulated and calcium is pumped back into SR.

Question 40

All fibers simultaneously activated when...

Answer 40

Motor neuron fires impulse

Question 41

Extent of control of muscle depends on...

Answer 41

Number of fibers within each motor unit

Question 42

Action potential is NOT...

Answer 42

Capable of directly exciting fibers

Question 43

AP causes chemical transmission and release of

Answer 43

Acetylcholine

Question 44

All fibers in motor unit contract and develop force at same time

Answer 44

All or none principle

Question 45

Short period of activation is called

Answer 45

Twitch

Question 46

Force summates if..

Answer 46

A second twitch elicited before complete relaxation

Question 47

Twitches merge and fuse..

Answer 47

Tetanus

Question 48

Maximal amount of force a motor unit can develop

Answer 48

Tetanus

Question 49

Fast twitch motor unit

Answer 49

Type ii

Question 50

Slow twitch motor unit

Answer 50

Type I

Question 51

Type ii twitch time..

Answer 51

Short

Question 52

Type I twitch time..

Answer 52

Long

Question 53

Type I Are..

Answer 53

Efficient, fatigue resistant, aerobic

Question 54

Type ii Are...

Answer 54

Inefficient, fatiguable, anaerobic

Question 55

Muscular force graded in two ways...

Answer 55

Variation in frequency. Recruitment

Question 56

Variation in frequency is...

Answer 56

As frequency increases, forces summate, force increases

Question 57

Recruitment

Answer 57

Varying number of activated motor units

Question 58

Maximal force production does not occur early in ROM if muscle is unloaded prior to muscle action

Answer 58

Preloading

Question 59

Recruitment patterns will vary depending on...

Answer 59

Joint position

Question 60

Preloading is important for...

Answer 60

Developing strength early in ROM, especially at high velocities

Question 61

Specialized sensory receptors in joints, muscles, tendons

Answer 61

Proprioceptors

Question 62

Job of proprioceptors...

Answer 62

Relay information about muscle dynamics to CNS

Question 63

Muscle length and rate of change

Answer 63

Spindles

Question 64

Spindles indicate..

Answer 64

Degree to which muscle must be activated in order to overcome a given resistance

Question 65

LocAted in tendons near myotendinous junctions

Answer 65

GTOs

Question 66

GTOs activated when

Answer 66

Tendon is stretched

Question 67

Neural input from GTOs...

Answer 67

Inhibits muscle activation. Protects against excessive tension