Ch. 09 - Muscles And Muscle Tissue

Front 1

1. skeletal

2. cardiac

3. smooth

Back 1

3 types of muscle tissue

Front 2

muscle fibers

Back 2

elongated skeletal and smooth muscle cells are also known as...

Front 3

skeletal muscle tissue

Back 3

muscle tissue attached to and covering the bony skeleton, responsible for body motility; 40% of body mass

Front 4

- voluntary

- striated

- multinucleate

Back 4

Describe skeletal muscle (movement, appearance, nucleus):

Front 5

cardiac muscle tissue

Back 5

muscle tissue forming the walls of the heart, help pump blood through the cardiovascular system

Front 6

- involuntary

- striated

- uninucleate or binucleate

Back 6

Describe cardiac muscle (movement, appearance, nucleus):

Front 7

smooth muscle tissue

Back 7

muscle tissue found in the walls of hollow organs, propels substances and maintains blood pressure

Front 8

- involuntary

- nonstriated, spindle-shaped

- uninucleate

Back 8

Describe smooth muscle (movement, appearance, nucleus):

Front 9

1. excitability

2. contractility

3. extensibility

4. elasticity

Back 9

4 special characteristics of muscle tissue

Front 10

excitability (responsiveness)

Back 10

the ability to receive and respond to a stimulus

Front 11

contractility

Back 11

the ability to shorten forcibly when stimulated

Front 12

extensibility

Back 12

the ability to extend or stretch

Front 13

elasticity

Back 13

the ability of a muscle cell to recoil and resume its resting length after stretching

Front 14

1. movement

2. posture

3. joint stability

4. body heat

5. protection

Back 14

5 most important functions of muscle

Front 15

fascia

Back 15

connective tissue that binds separate muscles into functional groups

Front 16

1. muscle

2. fascicle

3. muscle fiber

4. myofibril

5. myofilament

Back 16

5 levels (of rods) forming a muscle

Front 17

1. epimysium

2. perimysium

3. endomysium

Back 17

3 connective tissue sheaths surrounding muscle fibers (superficial to deep)

Hint 17

Front 18

epimysium

Back 18

the layer of dense irregular connective tissue surrounding the whole muscle

Hint 18

Front 19

fascicle

Back 19

a group of muscle fibers within each skeletal muscle; resembles a bundle of sticks

Hint 19

Front 20

perimysium

Back 20

the layer of fibrous connective tissue surrounding each fascicle

Hint 20

Front 21

endomysium

Back 21

the layer of areolar connective tissue surrounding each muscle fiber

Hint 21

Front 22

origin

Back 22

where muscle is attached to an immovable or less movable bone

Front 23

insertion

Back 23

where muscle is attached to a movable bone

Front 24

direct attachment (fleshy attachment)

Back 24

muscle attachment in which the muscle itself is fused to bone or cartilage

Front 25

indirect attachment

Back 25

common muscle attachment in which muscle connective tissue extends as a tendon or aponeurosis that anchors it to the skeleton

Front 26

tendon

Back 26

flexible but inelastic tissue attaching a muscle to a bone

Front 27

aponeurosis

Back 27

a sheet of fibrous tissue that takes the place of a tendon in sheetlike muscles with a wide area of attachment

Front 28

sarcolemma

Back 28

a muscle fiber's plasma membrane

Front 29

sarcoplasm

Back 29

a muscle fiber's cytoplasm

Front 30

1. glycosomes

2. myofibril

Back 30

2 special inclusions in muscle fiber sarcoplasm

Front 31

glycosomes

Back 31

granules of stored glycogen that provide glucose during muscle cell activity

Front 32

myoglobin

Back 32

a red pigment that stores oxygen in the sarcoplasm

Front 33

myofibrils

Back 33

hundreds to thousands of parallel-running rods that make up a single muscle fiber; 80% of cell volume

Hint 33

Front 34

A band

Back 34

the dark area of a myofibril

Hint 34

Front 35

H zone

Back 35

the light area in the middle of an A band on a myofibril

Hint 35

Front 36

M line

Back 36

the dark line running through each H zone on a myofibril, holds thick filaments together

Hint 36

Front 37

I band

Back 37

the light area of a myofibril

Hint 37

Front 38

Z disc

Back 38

the dark, "zig-zag" line intersecting each I band on a myofibril

Hint 38

Front 39

sarcomere

Back 39

the region of a myofibril between two Z discs; the functional unit of skeletal muscle

Hint 39

Front 40

myofilaments

Back 40

filaments that create the banding pattern of myofibrils

Hint 40

Front 41

thick filaments

Back 41

myosin-containing filaments (red) that extend the entire length of the A band, connect at the M line

Hint 41

Front 42

thin filaments

Back 42

actin-containing filaments (blue) that extend across the I band and part of the A band

Hint 42

Front 43

myosin

Back 43

protein with two globular heads that form cross bridges during muscle contraction

Hint 43

Front 44

cross bridges

Back 44

the point where thick and thin filaments link together during muscle contraction

Front 45

actin

Back 45

protein forming intertwined strands that serve as an attachment site for myosin's globular heads

Hint 45

Front 46

1. tropomyosin

2. troponin

Back 46

2 regulatory proteins found on thin filaments

Hint 46

Front 47

tropomyosin

Back 47

polypeptide strands spiraling around actin filaments to help stiffen and stabilize them

Hint 47

Front 48

troponin

Back 48

globular complex located on thin filaments that binds to actin, tropomyosin, and calcium ions

Hint 48

Front 49

elastic filament

Back 49

filament holding the thick filaments in place, prevents excessive stretching; composed of the protein titin

Front 50

1. sarcoplasmic reticulum

2. T tubules

Back 50

2 types of intracellular tubules that help regulate muscle contraction

Hint 50

Front 51

sarcoplasmic reticulum

Back 51

interconnecting tubules surrounding each myofibril; regulate intracellular calcium levels

Hint 51

Front 52

terminal cisternae

Back 52

large, perpendicular cross channels of sarcoplasmic reticulum at each A band-I band junction

Hint 52

Front 53

T tubules

Back 53

tubules from the sarcolemma that protrude deep in to the muscle fiber, increasing surface area; relay nerve impulses to all cells

Hint 53

Front 54

triad

Back 54

each terminal cistern-T tubule-terminal cistern pairing

Hint 54

Front 55

contraction

Back 55

the activation of myosin's cross bridges; muscle "shortening"

Front 56

sliding filament model

Back 56

states that during contraction the thin filaments slide past the thick ones so that their myosin and actin overlap to a greater degree

Hint 56

Front 57

action potential

Back 57

an electrical current generated by the sarcolemma

Front 58

neuromuscular junction (end plate)

Back 58

junction between a single muscle fiber and an axon's branches, connecting the brain and muscle

Hint 58

Front 59

synaptic cleft

Back 59

space separating an axon terminal and a muscle fiber; filled with glycoproteins and collagen fibers

Hint 59

Front 60

synaptic vesicles

Back 60

small membranous sacs in the axon terminal that deliver ACh (acetylcholine) to the synaptic cleft

Hint 60

Front 61

acetylcholine (ACh)

Back 61

neurotransmitter delivered by axons to muscle fibers; opens Na+ channels on the sarcolemma

Hint 61

Front 62

junctional folds (motor end plate)

Back 62

trough-like folds full of ACh receptors, increase surface area on the sarcolemma

Hint 62

Front 63

acetylcholinesterase

Back 63

the enzyme that breaks down ACh to its building blocks after it binds to ACh receptors; ends muscle contraction

Front 64

myasthenia gravis

Back 64

disease involving a shortage of ACh receptors, resulting in muscle weakness (such as droopy eyelids, difficulty swallowing)

Front 65

excitation-contraction coupling

Back 65

the sequence of events leading to muscle contraction, starting with the propagation of an action potential along the sarcolemma until the myofilaments slide

Front 66

rigor mortis

Back 66

muscle stiffening after death, due to lack of ATP (that ordinarily end contractions)

Front 67

muscle tension

Back 67

the force exerted by a contracting muscle on an object

Front 68

load

Back 68

the opposing force exerted on the muscle by the weight of an object

Front 69

motor unit

Back 69

one motor neuron and all the muscle fibers it innervates

Front 70

myogram

Back 70

a recording of contractile activity

Front 71

muscle twitch

Back 71

a motor unit's response to a single action potential of its motor neuron

Hint 71

Front 72

1. latent period

2. contraction

3. relaxation

Back 72

3 distinct phases of a twitch myogram

Front 73

graded muscle responses

Back 73

the varying degrees of muscle contractions, depend on the demands placed on the muscle

Hint 73

Front 74

TREPPE

Back 74

the staircase effect of muscle warm-up; increased calcium and heat makes enzymes more effective

Front 75

temporal (wave) summation

Back 75

successive twitches get stronger, and appear to ride on the shoulders of the previous twitch

Hint 75

Front 76

incomplete (unfused) tetanus

Back 76

a sustained but quivering muscle contraction

Hint 76

Front 77

complete (fused) tetanus

Back 77

a smooth, sustained muscle contraction; appears as a plateau on a myogram

Hint 77

Front 78

subthreshold stimuli

Back 78

stimuli that produce no observable contractions

Front 79

threshold stimulus

Back 79

the stimulus at which the first observable contraction occurs

Front 80

maximal stimulus

Back 80

the strongest stimulus that increases contractile force

Front 81

1. isotonic

2. isometric

Back 81

2 main categories of contractions

Front 82

isotonic contractions

Back 82

muscle length changes and moves a load, and tension remains relatively constant

Front 83

1. concentric

2. eccentric

Back 83

2 types of isotonic contractions

Front 84

concentric contractions

Back 84

contractions in which the muscle shortens and does work; ex. picking up a book, kicking a ball

Front 85

eccentric contractions

Back 85

contractions in which the muscle generates force as it lengthens; ex. walking up a steep hill

Front 86

isometric contractions

Back 86

contractions that occur when a muscle attempts to move a load that is greater than the force the muscle can develop; muscle neither shortens nor lengthens

Front 87

muscle tone

Back 87

the slightly contracted state of a relaxed muscle; helps with joint stability and posture

Front 88

1. direct phosphorylation

2. anaerobic pathway

3. aerobic pathway

Back 88

3 pathways of regenerating ATP during muscle activity

Hint 88

Front 89

direct phosphorylation

Back 89

regenerates ATP using creatine phosphate and ADP; creatine phosphate + ADP ---> creatine + ATP; 15 seconds worth

Front 90

creatine phosphate

Back 90

a unique high-energy molecule stored in muscle that helps regenerate ATP (by direct phosphorylation)

Front 91

anaerobic pathway

Back 91

relies on glycolysis to create ATP; 30-40 seconds

Front 92

glycolysis

Back 92

the breakdown of glucose by enzymes, releasing ATP and pyruvic acid

Front 93

lactic acid

Back 93

accumulates under anaerobic conditions; comes from pyruvic acid

Front 94

aerobic pathway

Back 94

relies on cellular respiration to create ATP; glucose + oxygen ---> carbon dioxide + water + ATP; hours

Front 95

aerobic endurance

Back 95

the length of time a muscle can continue to contract using aerobic pathways

Front 96

anaerobic threshold

Back 96

the point at which muscle metabolism converts to anaerobic glycolysis

Front 97

muscle fatigue

Back 97

the inability of a muscle to contract, even though it's still receiving stimuli

Front 98

excess postexercise oxygen consumption (EPOC)

Back 98

the extra amount of oxygen that the body must take in to restore its reserves after exercise

Front 99

1. number of muscle fibers

2. size of muscle fibers

3. frequency of stimulation

4. degree of muscle stretch

Back 99

4 factors affecting the force of muscle contraction (the number of cross bridges that attach)

Front 100

internal tension

Back 100

the force generated by cross bridges

Front 101

external tension

Back 101

the force transferred from cross bridges to the load

Front 102

1. muscle fiber type

2. load

3. recruitment

Back 102

3 factors affecting the velocity and duration of muscle contraction

Front 103

1. slow

2. fast

Back 103

2 types of muscle fibers (based on speed)

Front 104

1. oxidative

2. glycolytic

Back 104

2 types of muscle fibers (based on method of forming ATP)

Front 105

oxidative fibers

Back 105

muscle fibers that rely mostly on oxygen-using aerobic pathways for ATP

Front 106

glycolytic fibers

Back 106

muscle fibers that rely mostly on glycolysis for ATP

Front 107

1. slow oxidative

2. fast oxidative

3. fast glyolytic

Back 107

3 classes of muscle fibers

Front 108

endurance exercise

Back 108

exercises such as swimming, jogging, or biking; stamina, no hypertrophy, aerobic

Front 109

resistance exercise

Back 109

exercises such as weightlifting that pit muscles against high-resistance forces; strength, leads to hypertrophy, anaerobic

Front 110

cross training

Back 110

use of both aerobic and anaerobic exercises

Front 111

disuse atrophy

Back 111

degeneration and loss of muscle mass due to inactivity

Front 112

1. longitudinal layer

2. circular layer

Back 112

2 layers of smooth muscle

Hint 112

Front 113

peristalsis

Back 113

the propulsive action of smooth muscle, created by alternating contraction and relaxation of its layers

Front 114

variscosities

Back 114

bulbous nerve fiber ends that release neurotransmitter in to smooth muscle cells

Hint 114

Front 115

diffuse junctions

Back 115

the junctions between smooth muscle cells and variscosities

Hint 115

Front 116

caveolae

Back 116

pouchlike infoldings of the smooth muscle sarcolemma that intake extracellular fluid with high Ca2+ concentration; replace T tubules

Hint 116

Front 117

dense bodies

Back 117

act as anchoring points for thin filaments in smooth muscle; replace Z discs

Hint 117

Front 118

calmodulin

Back 118

the calcium-binding protein in smooth muscle; replaces troponin

Front 119

1. slow contraction

2. contraction in unison

3. anaerobic glycolysis

4. regulation

5. stretch

6. hyperplasia

Back 119

6 special characteristics of smooth muscle

Front 120

1. neural stimulation

2. hormones

3. local chemicals

Back 120

3 regulators of smooth muscle contraction

Front 121

1. unitary

2. multi unit

Back 121

2 main types of smooth muscle

Front 122

unitary smooth muscle (visceral muscle)

Back 122

type of smooth muscle forming the walls of all hollow organs except the heart

Front 123

multi unit smooth muscle

Back 123

type of smooth muscle in large airways and arteries, arrector pili, and internal eye

Front 124

myoblasts

Back 124

embryonic mesoderm cells from which all three types of muscle tissue derive

Hint 124

Front 125

muscular dystrophy

Back 125

a group of inherited muscle-destroying diseases that generally appear during childhood