Phys Exam 1 Flashcards
(180 cards)
1
Q
what is homeostasis
A
a dynamic and responsive process. maintains a range for optimal condition
2
Q
what are the steps of a response loop? (7)
A
- stimulus: change in environment
- sensor/receptor: detects change in environment
3.input (afferent): message sent to control center - integrating center: receives input signal
- output (efferent): message sent out
- target: cell receives message and initiates signal for change
- response: change occurs
3
Q
what is a neg. feedback loop and example
A
inhibits original stimulus. goes more towards equilibrium
thermoregulation
4
Q
what is a positive feedback loop and examples
A
enhance original stimulus. goes AWAY from equilibrium. MORE and MORE!
need outside factor to shut off
child birth and blood clotting
5
Q
what is a feed forward loop
A
helps anticipate/prepare for a stimulus (eating)
6
Q
where is cortisol produced?
A
adrenal glands
7
Q
what is cortisol known for
A
primary stress hormone
8
Q
what are some things cortisol does
A
- induces flight/fight (turns off non-essential things like digestion)
- increases glucose in bloodstream -> increases brain uptake of glucose
- reduces inflammation ->anti-inflammatory
- regulates bp
9
Q
what type of transport needs carrier proteins/pumps
A
facilitated diffusion and active transport
10
Q
a carrier protein is slow or fast
A
SLOW
11
Q
an ion channel is fast or slow
A
FAST
12
Q
osmolarity is what
A
number of solute particles dissolved in a volume of solution
13
Q
what is tonicity
A
compares a solution to a cell. tells us if the cell will shrink or swell
14
Q
if a cell swells, ECF?
A
hypotonic
15
Q
if a cell shrinks, ECF?
A
hypertonic
16
Q
two branches off PNS
A
autonomic and enteric (GI)
17
Q
difference between a neuron and nerve?
A
nerve has TONS of neurons.
18
Q
what does a glial cell do
A
polarization
19
Q
what does a neuron do
A
transmit signal
20
Q
what happens at the axon hillock
A
where AP originates
21
Q
what is the resting potential of a neuron
A
-70mV
more Na+ on outside
22
Q
what is action potential of a neuron
A
-55mV
voltage gated Na/K begin to open
23
Q
what is happening during repolarization
A
the K+ channels are still open while Na+ is closed so shoot way below.
24
Q
what happens during depolarization
A
Na+ ions come in FAST
25
what happens at top of AP
Na+ channels close and K+ begin to slowly open
26
what happens in order to go from hyperpolarization to resting state again
voltage gated K+ channels close and less K+ leaks out. becomes more positive (-70mV)
27
what is an absolute refractory period
NO depolarizations can happen during this time
28
what is a relative refractory period?
you would be a SUPER strong signal to depolarize again since we are in hyperpolarization (-80mV and not -70mV)
29
will the resting potential of CNS and PNS neurons vary?
YES!
due to hormones, temp, pressure, etc
30
what does a bigger and myelinated neuron mean in terms of speed?
FASTER!!!
31
what are the nodes of ranvier?
a gap in the myelin sheath where Na+ channels sometimes open
32
neuron to neuron communication: the AP causes what to enter the presyn, allowing the neurotransmitter to release
calcium enters
33
which one is faster: chemical or electrical synapses?
ELECTRICAL! its not as controlled though
34
what does a electrical synapse compose of
direct physical contact between the 2 neurons via a gap junction
allows for bidirectional movement
35
what does a chemical synapse compose of
presynaptic ending contains neurotransmitter and postsyn. has receptors of its membrane.
36
neuroplasticity
the amt of neurotransmitter and receptors presence can vary!
37
temporal summation
1 presyn. neuron generates AP. happens over time
38
spacial summation
MANY presyn. neurons generate AP
39
divergent pathway
one presyn. neuron branches to a bunch of post. syn neurons.
finger on someting hot
40
convergence pathway
many presyn. neurons converge to influence a SMALLER amt of postsyn. neurons
referred pain (pain in one part of your body is actually caused from a different part of your body
41
two types of neurotransmitter receptors
1. ionotropic. QUICK. ion channel
2. G-protein coupled receptors SLOW. no ion channel. second messengers
42
T/F: some neurotransmitters dont require a receptor
TRUE. super dangerous.
endocannabinoids and gasotransmitters (nitric oxide)
43
dopamine
inhibitory
reward/motivation
44
serotonin
inhibitory
regulates mood/anxiety/appetite
45
GABA
inhibitory
decreases anxiety and increases relaxation
46
noreprinephrine
both
alertness and arousal
47
glutamate
MAIN EXCITATORY
learning and memory
48
histamine
excitatory
increases wakefulness and decreases hunger
49
can a neurotransmitter have one effect on one cell and another on a different cell?
YES
50
What two systems are inseparable
nervous system and musculoskeletal
51
three types of muscle tissue
skeletal
cardiac
smooth
52
skeletal muscle characteristis
attaches to bone,skin,fascia
stratiated with light and dark bands
voluntary
STRONG and quick
53
cardiac muscle characteristics
striated
in-voluntary
auto-rhythmic bc of pacemaker cells
strong and quick
54
smooth muscle characteristics
attaches to hair follicles, walls of hollow organs and eye
non-striated
in-voluntary
strong and slow (digestion)
55
can skeletal muscles every be in-voluntary?
yes, shivering! produces heat
56
4 muscle properties
contractility
electrical excitability
extensibility
elasticity
57
what is tenosynovitis/tendonitis
inflammation due to overuse/strain
58
what type of injury is a contractile tissue injury?
strains NOT SPRAIN
59
where do tears often occur with tendons?
myotendinous junction
60
tendinosis/tendinophathy is from what?
NOT inflammation. tendon just doesnt tolerate stress
61
what is a sarcolemma
muscle fiber cell membrane
62
what is endomysium
surrounds the individual muscle CELL (including the sarcolemma)
also insulates the individual cells from one another.
rich in capillaries
63
what is perimysium
ensheathes muscle CELLS to form FASCICLES (bundle of muscle fibers/cells)
64
what is the epimysium
wraps around ENTIRE gross structure of muscle. (bundles of FASCICLES)
becomes continuous with muscle tendon
65
order of connective tissue coverings largest to smallest
epimysium > perimysium > endomysium > sarcolemma
66
difference between endomysium and sarcolemma
endomysium = layer outside cell membrane
sarcolemma = cell membrane
67
what is in a neurovascular bundle
Veins, arteries, nerve cells within peripheral nerves (connect the muscle cells to nervous system)
68
how do skeletal muscle cells become multi-nucleated
during embryonic development, multiple mesodermal stem cells fuse together to form a muscle fiber/cell.
Myogenesis
once mature, CANNOT DIVIDE
69
what is the structural and functional subunit of a muscle cell
Sarcomere
70
what are actin and myosin in
myofibril
71
actin is _______
myosin is ______
actin = thin
myosin = thick
72
where can we find myofilaments?
sarcoplasm (cytoplasm)
73
what is the sarcoplasmic reticulum
fluid filled system of membranous sacs encircling each myofibril within the muscle fiber/cell
74
where is Ca2+ stored until needed
sarcoplasmic rectiulum
75
where can we find mitochondria and glycogen deposits?
between the myofibrils in association with the SR
76
what is the sarcolemma
muscle fiber membrane where t-tubles are.
77
what do t-tubules do
rapidly convey AP to all myofibrils inside the muscle fiber
78
what type of fluid do t-tubles contain?
extra-cellular
79
what do myofibrils contain
myofilaments (actin/myosin)
80
what is the basic contractile component of a myofibril
sarcomere
81
Z-disc
separates one sarcomere from another
82
A-band
entire length of thick AND thin (that overlaps thick)
83
I-band
only THIN
84
H-zone
only THICK
85
M-line
in the middle of the H-zone. "middle line"
86
during contraction, what happens to the Z-disc
moves closer together
87
during contraction, what happens to the I-band
narrow
88
during contraction, what happens to the H zone
narrow
89
during contraction, what happens to the A band
DOESNT MOVE (myosin)
90
during contraction, what happens to the sarcomere
shortens
91
during contraction, what happens to the myofilaments
remain same length
92
2 contractile muscle proteins
actin and myosin
93
2 regulatory muscle proteins
1. tropomyosin
2. troponin
94
what does tropomyosin do
covers myosin binding sites on actin (long strings)
95
what does troponin do
the Ca2+ release causes shape change in troponin --> moves tropomyosin and allows binding between thick and thin filaments (disc part) Ca2+ binds to it
96
6 structural muscle proteins
1. titin
2. nebulin
3.alpha-actinin
4. myomesin
5.C-protein
6. dystrophin
97
what does titin do
anchors thick to Z lines. Stretches from Z-line to Z-line
LARGEST
98
what does nebulin do
aligns thin filaments
99
what does alpha-actinin do
bundles thin filaments into parallel arrays and anchors them at Z-line
100
what does myomesin do
holds thick filaments in place @ M-line (forms M-line)
101
what protein is the C protein most similar to
Myomesin
102
what does dystrophin do
cytoskeletal protein that links filaments to sarcolemma
103
rank
muscle fiber, sarcomere, muscle fascicle, myofibril
largest to smallest
muscle fascicle, muscle fiber, myofibril, sarcomere
104
what happens to your muscles that are immobilized by a cast
atrophy
105
steps of EC coupling
1. efferent motor signal (AP) from somatic motor neuron in peripheral nerve
2. NMJ events (chemical). ACh releases @ NMJ and causes depolarization (electrical) of muscle fiber/cell sarcolemma -> AP!
3.AP causes release of Ca2+ from SR in muscle fiber
4. CONTRACTION!!
5. active pump of Ca2+ back into SR = relaxation
106
can 1 neuron innervate many muscle fibers?
YES!
107
is the number of muscle fibers innervated based on need for fine motor control?
YES! eye vs leg
108
steps of nerve impulse at NMJ
1. release of ACh
2. opening of ACh-gated sodium channels
3. production of muscle cell AP
4. closing of ACh-gated channels - Na/K pump keeps intra Na+ LOW and K+ HIGH
109
what is ACh broken down by
acetylcholineterase
110
what is the cause of Myasthenia Gravis
ACh receptors on motor end plate are blocked by antibodies
AUTOIMMUNE!!
111
what is Bell's Palsy
facial nerve compression. inhibits the neurons ability to propagate an AP to NMJ bc the neuron cannot release ACh due to compression
112
what does botulinum do
blocks release of ACh from efferent motor neuron preventing muscle contraction
113
typical ATP storage in muscle cell is enough for how many twitches/contraction
5-8
114
what is ATP backup energy?
phosphocreatine.
transfer P to ADP during exercise to create more ATP
115
ATP IS REQUIRED FOR 3 THINGS
1. crossbridge formation and release (myofilament sliding)
2. active pump of Ca2+ ions from sarcoplasm back into SR
3. Na+/K+ pump to restore muscle fiber membrane potential
116
Describe Type I muscle
slow oxidative/slow twitch
high resistance to fatigue
aerobic
RED
natural runners have this
117
Describe Type IIA
fast oxidative-glycolytic / intermediate twitch
mod. amt of mito
mod. resistance to fatigue
ana or aerobic
LIGHTER RED
118
Describe Type IIB
FAST glycolytic / fast twitch
low # of mito
low resistance to fatigue
anaerobic
WHITE
not found in humans
119
what type of muscle do we alter with training
Type II A
120
as we age, what muscle types decrease
Type I and type II
121
as we age, what exercise is it important we do
RESISTANCE TRAINING
122
what 2 ways does strengthing occur?
1. Neural adaptations around 2 weeks. seem stronger but no physical changes
2. 8-12 weeks, muscle hypertrophy
123
do muscles ever get longer than their resting state?
NO! they contract and get shorter
124
what type of muscle is activated first?
type I then type II
125
what is contraction fatigue determined by
asynchronous recruitment (alternation of active motor units controlled by nervous system)
126
where are skeletal muscle strongest?
in their mid-position
127
muscles are
ALL OR NOTHING
128
what is isotonic contractions?
muscle changes LENGTH
129
concentric isotonic
muscle shortens under tension
biceps curl UP
130
eccentric isotonic
muscle LENGTHENS under tension
bicep curl on way DOWN
131
what are isometric contractions
muscle contraction/tension generated creates force to hold a load STATIONARY but isn't enough to move object''
muscle length does NOT change
muscle bulge shows sliding filament is occurring but NO movement
holding weight in L shape
132
what is the muscle spindle reflex? (MSR)
When muscles lengthen, the spindles are stretched. This stretch activates the muscle spindle which in turn sends an impulse to the spinal cord. This impulse results in the activation of more motor neurons at spinal level that send an impulse back to the muscle
133
what is descending inhibition in MSR
inhibitory interconnections within the spinal cord from the brain moderate the motor output
134
what are most CNS/UMN (upper motor neuron) injuries due to
a loss of descending inhibition. they will thus have an excessive MSR
135
what does no response on 1 side of the body tell us
PNS issue
136
what does no response on BOTH sides of the body tell us?
CNS issue
137
what is the golgi-tendon organ (GTO)
MUSCLE RELAXTION. opposite of MSR
When people lift weights, the golgi tendon organ is the sense organ that tells how much tension the muscle is exerting. If there is too much muscle tension the golgi tendon organ will inhibit the muscle from creating any force (via a reflex arc), thus protecting the you from injuring itself.
138
what happens when the GTO and MSR go against each other
twitch
139
what is clonus
cycling between MSR and GTO reflexes after a stretch
140
muscle spasticity is most likely to be caused from
loss of CNS inhibition of the muscle reflexes
**EXAM Q
141
are myokines similar to anything?
yes, hormones!
142
are smooth muscles
striated/non?
vol/in-vol?
how many nuclei?
non-striated
in-vol
one nuclei
143
are smooth muscle cells capable of mitosis? rengeration?
yes -> period shedding
144
does SM have troponin?
NO! calmodulin
145
unique features of SM (6)
1. can be stretched far -> bladder
2. can be layered in different directions -> GI
3. contractions happen slowly and last longer
4. uses less energy to maintain force. no fatigue. less mito needed
5. autonomic NS
6. Ca2+ for contraction comes from SR ANNNNDD extracellular fluid
146
what part of the NS controls SM
autonomic NS
147
does SM have sarcomeres?
NO! BUNDLES of actin/myosin
148
what is the nuclei shape in SM
corkscrewed
149
what are the actin/myosin attached to on SM
dense bodies on the membrane and in cytosol
150
what type of pattern are the intermediate filaments arranged in on SM
fish-net like
151
what are the 3 ways a SM can have a contraction
1. mechanical -> stretching
2. electrical -> ANS (parasym)
3. chemical -> hormones
152
does SM have t-tubules?
NO! Has caveolae. so it takes longer for the Ca2+ to reach the filaments and be reabsorbed
153
what structure is similar to t-tubules in SM
caveolae
flat-shaped invaginations of plasma membrane
154
how does calmodulin work on SM
the binding sites are blocked by caldesmon
when Ca2+-calmodulin COMPLEX bind to caldesmon, caldesmon moves away from myosin binding sites on actin molecule and cross-bridge forms
155
are cardiac muscle tissue
striated/non
vol/in-vol
have sarcomeres
striated
in-voluntary
have sarcomeres
156
in which ways are cardiac muscles similar to skeletal? (5)
1. striated and have sarcomeres
2. sarcolemma and t-tubules
3. signal goes to SR
4. release Ca2+ -> contraction
5. same mech as skeletal and same components (troponin, actin, etc)
157
in which ways is cardiac muscle similar to smooth muscle (4)
1. single nucleus
2. contains gap junctions
3. autonomic NS/hormonal control
4. in-voluntary
158
what features are unique to cardiac muscles (4)
1. shorter than skeletal
2. branched fibers
3. have intercalated disc
4. nuc. are spaced out
159
what is an intercalated disc?
connect adjacent cardiac muscle cells. contains junctions
160
what are the 3 types of junctions in cardiac cells and what do they do
1. gap junctions -> so it beats in synchrony/allows spread of depolarization
2. fascia adherens (adhering junction): hold muscle cells together
3. maculae adherentes (desmosome): reinforce fascia ^
2 and 3 work together!!
161
are the t-tubules in cardiac more or less organized than in skeletal? and where do they connect in each tissue?
MORE!
cardiac: Z-disc
skeletal: A-band to I-band
162
t-tubules associated with a diad and triad are where
diad -> cardiac
triad -> skeletal
163
are cardiac more or less vascularized than skeletal?
MORE!
164
what sets the rate of contraction in cardiac cells?
SA node -> fastest
165
skeletal, cardiac, smooth: cell size
skeletal - large elongated
cardiac- short and narrow
smooth- short and elongated
166
skeletal
cardiac
smooth
connective tissues
skeletal: epi, peri, endomysium
cardiac: endomysium
smooth: endomysium, sheaths and bundles
167
skeletal:
cardiac:
smooth:
single or multinucleated
skeletal: many
cardiac: one
smooth: one
168
skeletal:
cardiac:
smooth:
straited?
skeletal: yes
cardiac: yes
smooth: no
169
skeletal:
cardiac:
smooth:
cell junctions
skeletal: none
cardiac: intercalated discs and junctions
smooth: gap junctions
170
skeletal:
cardiac:
smooth:
unique features
skeletal: well developed sER and t-tubules
cardiac: intercalated discs
smooth: dense bodies, caveolae and cytoplasmic vesicles
171
skeletal:
cardiac:
smooth:
innervation type
skeletal: vol
cardiac: in-vol
smooth: in-vol
172
skeletal:
cardiac:
smooth:
efferent innervation
skeletal: somatic
cardiac: autonomic
smooth: autonomic
173
skeletal:
cardiac:
smooth:
regulation of contraction
skeletal: Ca to troponin
cardiac: Ca to troponin
smooth: phosphorylation of myosin light chain (Ca2+-calmodulin complex)
174
skeletal:
cardiac:
smooth:
mitosis?
skeletal: limited
cardiac: no
smooth: yes
175
What is the equivalent of t-tubules in smooth muscle
Caveolae
176
What is the equivalent of troponIN in smooth muscle
CalmoduLIN
177
What is the equivalent of tropomyosin in smooth muscle
Caldesmon
178
What most closely controls RMP in neurons
K
179
Ipsp ions
Cl. Hyper polarizes
180
Epsp ions
Na or Ca. Depolarization
