Muscle Tissue

Question 1

Skeletal Muscle

Answer 1

• longest cell type
• voluntary
• multinucleate
• striated

Question 2

Cardiac Muscle

Answer 2

• involuntary
• striated
• uninucleate
• intercalated disc

Question 3

Smooth Muscle

Answer 3

• not striated
• walls of hollow organs (viscera)
• involuntary
• uninucleate
• slow & sustained contractions

Question 4

4 muscle functions

Answer 4

1. movement
2. maintaining posture
3. stabilizing joints
4. generates heat

Question 5

muscle cells are called…

Answer 5

fibers

Question 6

4 functional characteristics

Answer 6

1. excitability/irritability
2. contractility
3. extensibility
4. elasticity

Question 7

which functional characteristic has the ability to respond to stimuli usually by neurotransmitter and is the response from electrical generation from Ionic Gradient

Answer 7

Excitability/Irritability

Question 8

Which functional characteristic has the ability to shorten

Answer 8

contractility

Question 9

which functional characteristic has the ability to stretch/extend

Answer 9

extensibility

Question 10

which functional characteristic has the ability to regain resting length after stretching

Answer 10

elasticity

Question 11

insertion

Answer 11

more moveable

Question 12

orgin

Answer 12

less moveable

Question 13

direct attachment

Answer 13

epimysium -> periosteum

Question 14

indirect attachment

Answer 14

epimysium -> C.T.

Question 15

is indirect or direct attachment more common?

Answer 15

indirect

Question 16

what is the fiber’s cytoplasm called

Answer 16

sarcoplasm

Question 17

sarcoplasm is high in ____ & ____

Answer 17

glycogen & myoglobin

Question 18

what are the rodlike structures that run entire length of cell and are densely packed

Answer 18

myofibrils

Question 19

what are the striations made up of

Answer 19

repeating series of bands (dark & light)

Question 20

which striation is dark, polarized visible light

Answer 20

A-Band

Question 21

which striation is light & nonpolarized

Answer 21

I-Band

Question 22

when is the H zone visible

Answer 22

in relaxed muscle

Question 23

where proteins help hold myosin in place

Answer 23

M Line

Question 24

these help hold actin in place

Answer 24

Z Discs

Question 25

what is the smallest contractile unit of muscle

Answer 25

sarcomere

Question 26

each thick filament is surrounded by ___

Answer 26

6 thin filaments

Question 27

thick filaments are made of____

Answer 27

myosin

Question 28

the tail of thick filaments consist of 2 _____

Answer 28

interwoven heavy polypeptide chains

Question 29

thick filaments have ____ & _____

Answer 29

ATP binding sites & ATPase

Question 30

thin filaments are made of ____

Answer 30

actin, troponin, tropomyosin

Question 31

actin is made of ___

Answer 31

polypeptide globular actin

Question 32

what spirals around “actin core” to hell straighten it & blocks the actin active sites at rest

Answer 32

Tropomyosin

Question 33

what is another protein that holds tropomyosin in place

Answer 33

Troponin

Question 34

what surrounds each myofibril like a sleeve, forms large cross channels called terminal cisternae, covers where the A & I bands meet, & regulates intracellular levels of Ionic Calcium

Answer 34

SR (Sarcoplasmic Reticulum)

Question 35

what enhances cellular communication, is like penetrating wires between myofibrils, & run between terminal cisternae forming triad relations

Answer 35

T-Tubules (Transverse Tubules)

Question 36

What happens during the Sliding Filament Theory

Answer 36

* myosin heads attach to actin sites & act like tiny ratchets pulling thin filaments towards the M Line * distance between Z Discs shorten * A Bands move closer together * H Zone disappears

Question 37

what is the spot where an individual axon ending meets/joins w a single muscle fiber

Answer 37

neuromuscular junctions

Question 38

what usually exists between a neuromuscular junction

Answer 38

a synaptic cleft

Question 39

what is a single action potential of a motor neuron & its effect on a motor unit

Answer 39

the muscle twitch

Question 40

what are the 3 phases of the muscle twitch

Answer 40

1. Latent period 2. Period of contraction 3. Period of relaxation

Question 41

the graded response (degree of contraction) is based on ____

Answer 41

the frequency/strength of the signal

Question 42

muscle tone =

Answer 42

low levels of contractility

Question 43

Isotonic Contraction

Answer 43

* muscle shortens (concentric contraction or lengthens eccentric) * a load is moved

Question 44

Isometric Contractions

Answer 44

•no change in length (wall sit)

Question 45

fine motor control = ___ motor units

Answer 45

small

Question 46

gross motor control = ___ motor units

Answer 46

large

Question 47

slow (oxidative) fibers

Answer 47

* red fibers due to myoglobin | * many mitochondria, slow speed, & long duration

Question 48

Fast (Oxidative) Fibers

Answer 48

* intermediate fibers (red to pink) | * actions between slow & glycolytic

Question 49

Fast (Glycolytic) Fibers

Answer 49

* white fibers | * fast speed, intense movements

Question 50

degenerative size reduction due to inactivity

Answer 50

atrophy

Question 51

the inability of a muscle to contract due to prolonged exercise

Answer 51

fatigue

Question 52

the increase in tissue size

Answer 52

hypertrophy

Question 53

what kind of exercise increases capillaries & mitochondria, causes the fibers to synthesize more myoglobin, & increases muscles capacity for cellular respiration

Answer 53

aerobic exercise