Anatomy Muscle Flash Cards

Front 1

Functions of Muscular System

Back 1

Movement: think of muscles as ropes, muscles can only contract, shorten in length, pull, muscles cannot push
Heat production
Posture and body support

Front 2

Types of Muscles

Back 2

Smooth: non striated, involuntary
Cardiac: striated, involuntary
Skeletal: striated, voluntary

Front 3

Basic Properties of Muscles

Back 3

Irritability: response to stimulus
Contractality: active
Extensibility: passive
Elasticity: muscles return to original length

Front 4

Skeletal Muscle Attachment: Origin

Back 4

doesn't move, muscle attachment more proximal

Front 5

Skeletal Muscle Attachment: Insertion

Back 5

attachment that is more distal, mobile

Front 6

Belly

Back 6

Body, main region that shortens and thickens when muscle contracts

Front 7

Fascicle

Back 7

Bundle of muscle cells, makes up muscle

Front 8

Epimysium

Back 8

dense irregular, surrounds skeletal muscle

Front 9

Peromysium

Back 9

surrounding fascicle

Front 10

Muscle Cell

Back 10

Muscle fiber, has a lot of nuclei that is pushed to outside

Front 11

Endomysium

Back 11

Membrane that surrounds the cell

Front 12

Sarcolemma

Back 12

Cell membrane of muscle cell

Front 13

Sarcoplasm

Back 13

cytoplasm of muscle cell

Front 14

Satellite Cells

Back 14

repair muscle cells after being damaged

Front 15

Myofibril

Back 15

made of myofilament (Thick-myosin, thin-actin)

Front 16

Sarcoplasmic Reticulum

Back 16

smooth endoplasmic reticulum in a muscle fiber, stores calcium ions needed for muscle contraction

Front 17

Terminal Cisternae

Back 17

expanded ends of the sarcoplasmic reticulum that are in contact with the transverse tubules, site of calcium ion release to promote muscle contraction

Front 18

Thick Filament

Back 18

Fine protein myofilament composed of bundles of myosin, bin to actin and and cause contraction

Front 19

Thin Filament

Back 19

Fine protein myofilament composed of actin, proponin and tropomyosin

Front 20

Actin

Back 20

double stranded contractile protein, bind to myosin to cause contraction

Front 21

Tropomyosin

Back 21

double stranded regulatory protein, covers the active sites on actin, preventing myosin from binding to actin

Front 22

Troponin

Back 22

Regulatory protein that holds tropomyosin in place and anchors to actin, when calcium ions bind to one of its subunits, this moves the tropomyosin off the actin active site and initiates muscle contraction

Front 23

Titin

Back 23

Filaments of an elastic protein, help return myofilaments to resting position after contraction, maintain positions of myofilaments in sarcomere

Front 24

A band

Back 24

dark band, over lap and repetition of thick and thin, gets bigger when contracts

Front 25

M Line

Back 25

middle of the thick filaments

Front 26

Z Disc

Back 26

Boundary of sarcomeres, connect the thin filaments to each other

Front 27

H Zone

Back 27

Area in the A band that doesn't have actin filaments

Front 28

Myofibril

Back 28

cylindrical structures that are responsible for contraction

Front 29

I Band

Back 29

light band, no over lap of thin and thick, gets smaller in contraction

Front 30

Sarcomere

Back 30

functional unit, areas in between z discs, where microfilament are organized

Front 31

Synaptic Knob

Back 31

end of axon terminal, rough ER (form vesicles, make protein)

Front 32

Motor Unit

Back 32

axon terminals of motor neurons and muscle fibers

Front 33

Synaptic Cleft

Back 33

Separates muscle and neuron

Front 34

Order of Events in Muscle Contraction

Back 34

1)Nerve impulse triggers release of ACh at neuromuscular junction, ACh binds to motor end plate receptor initiating a muscle impulse in the muscle fiber
2)The muscle impulses spreads quickly along to tubules causin release of calcium ions from terminal cisternae into the sarcoplasm

Front 35

Muscle contraction

Back 35

1)Atp binds to myosin head, myosin releases actin
2) ATP turns into ADP and phosphate group, releases energy, cocks the myosin protein to high energy shape
3) Phosphate group released myosin, pushes actin filament, power stroke
4)ADP released

Front 36

Muscle twitch

Back 36

Full stiumulation-contraction-relaxation cycle

Front 37

What does the amount of tension a muscle fiber produces during a twitch depend on?

Back 37

How many crossbridge attachments it forms

Front 38

What does number of crossbridge formation depend on?

Back 38

quantity of myofibrils per muscle fiber, number of byofilament per myofibril, length of muscle fibers when contraction begins, rate or frequency fiber is stimulated

Front 39

Latent Period

Back 39

begins at stimulation, lasts around 2 miliseconds, action potential floods over the carcolemma, causing calcium to release from sarcoplasmic reticulum , no tension

Front 40

Contraction Phase

Back 40

lasts around 100 miliseconds, crossbridge formation causes tension to increase to a maximum

Front 41

Relaxation Phase

Back 41

tension decreases as crossbridges detach, titin fibers in sarcomeres cause muscle fibers to return to resting length

Front 42

Summation

Back 42

muscle fiber doesn't have time to relax completely before another action potential causes it to contract again

Front 43

incomplete tetanus

Back 43

muscle fiber reaches maximum contraction, less time is allowed for relaxation (and rest) before a new action potential arrives

Front 44

complete tetanus

Back 44

muscle fiber doesn't have time to relax between action potentials, maximum tension maintained

Front 45

What does the amount of tension produced by skeletal muscle as a whole depend on?

Back 45

how frequently the muscle is stimulated (summation and tetanus)
How many muscle fibers are stimulated

Front 46

Recruitment

Back 46

force generated by a muscle can be increased by recruiting more motor units

Front 47

Asynchronous recruitment

Back 47

partial avoids fatigue in submaximal contractions by alternating the action of the muscle's motor units, alternates muscles being used

Front 48

Muscle fatigue

Back 48

motor units fail one by one, force of muscle contraction gradually decreases

Front 49

Muscle tone

Back 49

resting tensions, more frequently and more intensely muscles are used, high tone

Front 50

Atrophy

Back 50

muscles that are not regularly stimulated, muscle fibers become weaker and smaller, inactivity continues, muscle fibers die

Front 51

What is ATP used for?

Back 51

cross bridge action
Calcium Pump
Sodium/Potassium pump

Front 52

At Rest

Back 52

ATP Generation greater than ATP consumption

Front 53

During excercise

Back 53

ATP Gen=ATP consumption

Front 54

Creatine phosphate

Back 54

more stable than ATP, used to phosphorylate ADP to ATP during contraction

Front 55

Aerobic Cellular Respiration

Back 55

Glucose + Oxygen yields Carbon dioxide + Water + 32 ATP
able to crank out more ATP than resting cell

Front 56

Anaerobic Respiration

Back 56

Glucose yields 2 pyruvate (which yields 2 ATP)