Muscle Physiology

Front 1

functions of muscle

Back 1

movement, stability, controls openings and passageways & heat production

Front 2

3 layers of connective tissue that surround muscle fibers/cells, muscle fascicles & muscles

Back 2

Endomysium = inside
Perimysium = middle
Epimysium = outside

Front 3

superficial & deep fascia

Back 3

fascia sorrounds muscle fibers, allows for muscles to glide over each other & allows for muscles to stretch 2 layers

Front 4

origin & insertion

Back 4

origin of the muscle is the end of the muscle attaching to the fixed bone : insertion attached to moving part of the joint

Front 5

function of tendons & aponeuroses

Back 5

a cord or band of inelastic tissue connecting a muscle with its bony attachment, aponeuroses similar just flat and broad

Front 6

intrinsic vs extrinsic muscles

Back 6

intrinsic = stay in one region
extrinsic = action is outside of region

Front 7

levers, mechanical advantage, disadvantage

Back 7

class 1 = either
class 2 = mech advantage
class 3 = mech disadvantage

Front 8

class 1 lever

Back 8

force - folcrum - load

head tilting, like a crow bar or teeter totter

Front 9

class 2 lever

Back 9

folcrum - load - force

standing on tippy toes, like a wheelbarrow

Front 10

class 3 lever

Back 10

folcrum - force - lever

elbow, like a catapult

Front 11

prime mover/ agonist

Back 11

muscles that are primarily responsible for generating a specific movement

Front 12

synergist

Back 12

assist in performing, the same set of joint motion as the agonists

Front 13

antagonist

Back 13

used to describe a muscle that acts in opposition to the agonist and is returns a limb to its initial position

Front 14

fixator

Back 14

The fixators prevents any unecessary movement,

Front 15

components of a muscle cell (myofibril or muscle fiber)

Back 15

sarcolemma, T tubule, sarcoplasmic reticulum, myofibril, sarcomere

Front 16

sarcolemma

Back 16

= cell membrane, essential in cell stimuli, and fuses to tendons at the ends of the muscle cells

Front 17

T tubule

Back 17

small tubules which run transversely striated muscle fiber and electrical impulses are transmitted

Front 18

sarcoplasmic reticulum

Back 18

a system of tubules that surround muscle fibrils, release calcium ions then absorb them.

Front 19

myofibril

Back 19

a muscle fibril, one of the slender threads of a muscle fiber, composed of numerous myofilaments.

Front 20

sarcomere

Back 20

the contractile unit of a myofibril; sarcomeres are repeating units, delimited by the Z bands, along the length of the myofibri

Front 21

3 types of muscle

Back 21

skeletal, cardiac, smooth

Front 22

structures or the sarcomere

Back 22

myosin, actin, tropomyosin, troponin

Front 23

myosin

Back 23

interacts with the protein actin to contract a muscle or cell movement. Myosin is present in the myofibrils

Front 24

actin

Back 24

localized in the I band of the myofibrils; acting along with myosin, it is responsible for contraction and relaxation

Front 25

tropomyosin

Back 25

actin binding protein, regulates actin, which regulates the muscle from contracting and relaxing

Front 26

troponin

Back 26

Troponin is attached to the protein tropomyosin and lies within the groove between actin filaments in muscle tissue. In a relaxed muscle, tropomyosin blocks the attachment site for the myosin crossbridge, thus preventing contraction. When the muscle cell is stimulated to contract by an action potential, calcium channels open in the sarcoplasmic reticulum and release calcium into the sarcoplasm. Some of this calcium attaches to troponin, causing a conformational change that moves tropomyosin out of the way so that the cross bridges can attach to actin and produce muscle contraction.

Front 27

components of muscle striations

Back 27

Z line, M line, A band, H band, I band.

Front 28

Z line

Back 28

zig zag ends of the sarcomere

Front 29

M line

Back 29

Mid line direct center of sarcomere

Front 30

A band

Back 30

Thick filament band that is fixed and does not move, connected to cross bridge

Front 31

H band

Back 31

center zone around the M line

Front 32

I band

Back 32

moving piece thin filament slides along the thick filament by way of the cross bridge

Front 33

neuromuscular junction

Back 33

contraction the signal passes through the neuromuscular junction via the neurotransmitter acetylcholine.

Front 34

muscle contraction components

Back 34

motor neuron, axon, neurotranmitter, synapse, neuromuscular junction

Front 35

motor unit

Back 35

When a motor unit is activated, all of its fibers contract.
effects 2 types slow twitch and fast twitch

Front 36

axon

Back 36

long, slender projection of a neuron, that conducts electrical impulses away from the neuron's cell body

Front 37

neurotransmitter

Back 37

Neurotransmitters are endogenous chemicals which transmit signals from a neuron to a target cell across a synapse

Front 38

synapse

Back 38

a junction that permits a neuron to pass an electrical or chemical signal to another cell.

Front 39

role of acetylcholine

Back 39

binds to acetylcholine receptors muscle fibers, it opens sodium channels in the cell membrane.

Front 40

role of aceytlcholinesterase

Back 40

enzyme that activity serves to terminate synaptic transmission.

Front 41

action potential

Back 41

when the threshold is met voltage-gated ion channels open
sodium in potassium out.

Front 42

phases of muscle twitch

Back 42

latent, contraction, relaxation

Front 43

latent phase

Back 43

stimulus application until the muscle begins to contract. no activity there are electrical and chemical changes

Front 44

contraction phase

Back 44

the muscle fibers shorten, the tracings will show during this phase

Front 45

relaxation

Back 45

downward curve when the muscle is going back to its original state of relaxation and will once again lengthen

Front 46

absolute vs relative refractory periods

Back 46

absolute = not possible action potential
relative = unlikely action potential but possible

Front 47

contraction types

Back 47

twitch, treppe, wave summation, tetany