Chap 9 Flashcards
1
Q
muscle increases in size in response to exercise is called;
A
hypertrophies
2
Q
muscle that is not used decrease in size called;
A
atrophies
3
Q
general terms for connective tissue sheets;
A
fascia
4
Q
3 muscle types;
A
- cardiac
- skeletal
- smooth
5
Q
cylindrical, branched/intercalated cells with a single centrally located nucleus;
A
cardiac muscle cells
6
Q
- spindle-shaped cells with a single centrally located nucleus
- gap junction join them together
- autorhythmic
A
smooth muscle cells
7
Q
long, cylindrical cells with many peripherally located nuclei;
A
skeletal muscle cells
8
Q
sodium-potassium pump;
A
- pumps sodium out of the cell against its concentration gradient
- uses ATP
9
Q
ability of muscle to recoil to its original length after been stretched;
A
elasticity
10
Q
ability of muscle to respond to stimulus;
A
excitability
11
Q
ability of muscle to stretch beyond its normal length and still be able to contract;
A
extensibility
12
Q
heavy connective tissue layer surrounding each fasciculus;
A
perimyseum
13
Q
dense collagenous connective tissue that surrounds the entire muscle;
A
epimysium
14
Q
dense irregular collagenous connective tissue that separates and compartmentalizes individual muscles or groups of muscles;
A
fascia
15
Q
4 property of muscle;
A
- contractility
- excitability
- extensibility
- elasticity
16
Q
- contractility =
A
ability of a muscle to shorten with force
17
Q
- excitability =
A
capacity of muscle to respond to a stimulus
18
Q
- extensibility =
A
muscle can be stretched to its normal resting length and beyond to a limited degree
19
Q
- elasticity =
A
ability of muscle to recoil to original resting length after stretched
20
Q
when cell is “polarized” =
A
there is a difference in the charge between the cytoplasm and the extracellular fluid surrounding it.
21
Q
type of muscle found in the wall of blood vessels=
A
smooth muscle
22
Q
resting cell is more ______ than the extra cellular.
A
negative
23
Q
single action potential;
A
- limited Na+ channels open and Na+ moves into the cell
- threshold reached
- more Na+ channels open and Na+ moves into the cell
- depolarization
- K+ channels open and K+ leaves the cell
- repolarization
24
Q
Na+ flow into the cell if;
P.277
A
- cytoplasm is very negative (-70mv), extracellular is positive
- concentration of Na+ is higher in the extracellular fluid than in the cytoplasm
25
cell bodies of motor neurons are located in;
brain and spinal cord
26
a single very long (can be 30cm) cylindrical cell with many peripherally located nucleus =
skeletal muscle fiber
27
_________ can stimulate/inhibit the production of an action potential in the postsynaptic membrane (sarcolemma) by binding to ligand-gated ion channel. P.385
=neurotransmitter
28
aerobic respiration=
glucose
fatty acids
amino acids
29
both fast-twitch and slow twitch muscle fibers can increase _______ by exercise and training.
- capacity
- efficiency
- size (fast)
- strength (slow)
30
method that can produce up to molecules for each glucose molecule is;
aerobic respiration
31
action/function of all muscle cells is;
contract
32
voltage of a repolarizing neuron or muscle fiber becomes more ______.
negative
33
protein channels connecting cardiac muscle cells which allow action potentioals to pass from cell to cell are called;
gap junctions
34
a whole muscle is innervated by;
more than 1 neuron
35
smooth muscle properties;
- relatively constant tension
| - autorhythmic contractions
36
action potential travels from the brain or spinal cord along the axons to;
across the plasma membrane by stimulating the production of another action potential
37
intercalate means=
=insert between or among element (branched cardiac muscle fiber)
38
a type of smooth muscle that contracts as many independent units and has fewer gap junctions is;
multiunit smooth muscle
39
electrically excitable cells are _______.
polarized
40
polarized means;
electrical charge difference exists across each plasma membrane
41
3 location of fatigue;
- central nervous system = psychological fatigue/emotional state
- muscle fiber = muscular fatigue/Ca+ imbalances by dropped ATP level
- neuromuscular junction = synaptic fatigue/too many ACh, empty synaptic vesicles
42
7 functions of the muscular system;
1. movement of the body (skeletal)
2. maintenance of body posture (skeletal)
3. respiration (skeletal)
4. production of body heat (skeletal)
5. communication (skeletal)
6. constriction (compress) of organs and vessels (smooth)
7. contraction of the heart (cardiac)
43
during Depolarization of action potential, the membrane potential voltage becomes _____
positive
44
during Repolarization of action potential, the membrane potential voltage becomes _____
negative
45
organelles located within the presynaptic terminals and contain neurotransmitter are called;
synaptic vesicles
46
each action potential affects;
only a small area of the plasma membrane at a time
47
the force of contraction is increased in 2 ways:
1. summation (within the muscle)
| 2. recruitment (number of muscle fibers)
48
muscle relaxation;
occurs when acetylcholine is no longer released at the neuromuscular junction.
1. action potential stops along the sarcolemma stops Ca+ release, Ca+ is actively transported back into the sarcoplasmic reticulum.
2. Ca+ diffuses away from the troponin molecules.
3. troponin-tropomynosin complex and reestablishes its position, which blocks the active sites on the actin molecules.
4. cross-bridges cannot re-form once they have been released, and the muscle relaxes.
49
negative membrane potential indicates that the area with more negative charge is on the _____ of the membrane.
inside
50
depolarization of action potential is caused by;
- the membrane reached threshold
| - voltage-gated sodium channels open
51
2 types of smooth muscle;
- visceral =has numerous gap junctions, action potential pass directly cell to cell (digestive, reproductive, urinary tracts)
- multiunit =has fewer gap junctions, cell or group of cells act as independent unit (walls of blood vessels, arrector pili muscles, iris of the eye)
52
arrector pili muscle=
cause hair to stand (locates in dermis)
53
muscle fiber twitch;
- very short in duration
- does not produce enough tension to perform any work
- contains a contraction and relaxation phase
54
"cocking" of myosin head, hydrolysis of ATP, power stroke occur during ______ phase of skeletal muscle contraction
contraction
55
slow-twitch oxidative (SO) (type 1) fiber type
- high aerobic capacity
| - highest resistance to fatigue
56
fast-twitch oxidative glycolytic (FOG) (type 2a) fiber type
high myoglobin and glycogen concentration with both intermediate aerobic capacity and high anaerobic capacity
57
fast-twitch glycolytic (FG) (type 2b) fiber type
fibers with fewest capillaries and mitochondria and highest anaerobic capacity
58
action potential in the motor neuron generates an action potential in each of the muscle fibers of its ________.
motor unit
59
2 types of isotonic contractions (the amount of tension produced by the muscle is constant during contraction but the length of the muscle changes)
- concentric contraction =lifting a loaded backpack from the floor
- eccentric contraction =slowly lowers a heavy weight
60
mechanism of ATP production that requires oxygen is;
aerobic respiration
61
thin myofilament =
- actin
- troponin
- tropomyosin
62
during a single contraction, each myosin molecule undergoes the cycle of cross-bridge formation, movement (power stroke), release and return (recovery stroke) many times, this called;
cross-bridge cycling
63
protein in the muscle fiber that stores oxygen and releases oxygen when needed is called =
myoglobin
64
receptor molecules that stimulate smooth muscle contractions open ____ or _____ channels
Na+ / Ca2+
65
when muscle fiber relaxes, ATP is needed to;
- maintain the normal concentrations of Na+ and K+ across the sarcolemma
- detach the myosin head from actin
- transport of Ca2+ into the sarcoplasmic reticulum
66
a modified form of smooth endoplasmic reticulum located in muscle cells is;
sarcoplasmic reticulum
67
creatine phosphate is used to store energy that can be used to synthesize;
ATP
