Physiology Test 2 Set A Flashcards
(68 cards)
1
Q
What are the communication and control systems of the body
A
nervous and endocrine systems
2
Q
all glands that secrete hormones make up the
A
endocrine system
3
Q
collects information, analyses it and generates co-ordinated output
A
nervous system
4
Q
cells adapted to generate and propagate an electrical signal
A
neurons
5
Q
four functional regions of a neuron
A
- dentrites
- cell body
- axon
- presynamptic terminals
6
Q
non-neuron nervous cell thatprovide physical support, nutrition, to neurons
A
glial cells
7
Q
type of glial cell that looks for foreign invaders
A
microglia
8
Q
an individual cell
A
neuron
9
Q
a bundle of axons in the pns
A
nerve
10
Q
cell bodies make up the
A
grey matter
11
Q
myelin makes up the
A
white matter
12
Q
relay sensory signals to integrative sites
A
afferent neurons
13
Q
relay control signals from integrative centers to target cells under nervous control
A
efferent neurons
14
Q
relay signals entirely within the central nervous system
A
interneurons
15
Q
everything in the nervous system starts with the
A
receptor
16
Q
what makes up the CNS
A
brain and spinal cord
17
Q
clusters of cell bodies in the CNS
A
nuclei
18
Q
bundles of axons
A
tract or pathway
19
Q
what makes up the PNS
A
all nerves extending from the CNS to the rest of the body
20
Q
clusters of cell bodies in the PNS
A
ganglia
21
Q
stimulates voluntary muscles
A
somatic motor neurons
22
Q
stimulates involuntary muscles and tissues
A
autonomic motor neurons
23
Q
processes done at high activity (stress)
A
sympathetic nervous system
24
Q
processes done at rest (housekeeping)
A
parasympathetic nervous system
25
describe the organization of mammalian sympathetic nervous system
short preganglionic uses ach, long postganglionic releases norepi
26
describe the organization of mammalian parasympathetic nervous system
long preganglionic and short postganglionic both use Ach
27
sympathetic does what
```
increases heart rate
releases catacholamines from chomaffin cells
stimulates sweat
relaxes bladder
inhibits digestion
relaxes airways
dilates pupils
constricts blood vessels
```
28
parasympathetic division does what
```
constricts pupils
stimulates salvation
slows heart rate
stimulates digestion
dilates blood pressure
```
29
no further change in electrical potential and no further change in the ion concentration across the membrane
electrochemical equilibrium
30
equation applies to only one ion at a time and only to ions that can cross the membrane
Nernst equation
31
specific cell properties must be considered when determining the equilibrium potential of specific ions
1. principle of electrical neutrality
| 2. osmotic balance
32
What factors determine the resting membrane potential
1. unequal distribution of inorganic ions
| 2. relative ion permeabilities
33
determined by the properties of the ionic pores or channels in a membrane
ionic permeability
34
the equation that gives the quantitative relation between membrane potential, ion concentrations, and permeabilities
the goldman equation
35
the Em in a cell is generally closer to sodium or potassium
potassium
36
Why is Em closer to potassium
this is the ion that is the most permeable to the membrane
37
resting membrane potential for a neuron is around
-65mV
38
cell capable of modulating their membrane potential in response to stimulation from their environment
excitable cells
39
six characteristics of an action potential
1. triggered by a depolarization
2. threshold must be reached in order to trigger action potential
3. all or nothing events
4. propagates without decrement through a neuron
5. at peak Em becomes inside positive
6. there is a brief period called the absolute refractory period when another action potential cannot be fired
40
where on the neuron is the action potential generated
the axon hillock
41
when the membrane potential of a cell becomes more negative
hyperpolarizing
42
when the membrane potential of a cell becomes more positive
depolarizing
43
threshold potential is determined by
the density of voltage-sensitive sodium channels
| connection between depolarization and opening of sodium channels
44
two important factors cause the membrane potential to return to rest following depolarization
depolarization induced increase in permeability of sodium is transient
a delayed voltage dependent increase in potassium
45
closed when membrane potential is equal or more negative than the usual resting potential, preventing sodium from entering and responses quickly in response to depolarization
m gate voltage Na channel
46
open at resting membrane potential, closes in response to depolarization slowly, and leads to a decrease in sodium permeability
h gate voltage Na channel
47
whats going on in the resting membrane potential
potassium leak channels are open, voltage gated channels are closed
48
what is going on in the rising phase of the action potential
when threshold is reached m gated voltage sodium channels open leading to depolatization of the membrane which leads more Na channels to open which causes more depolarization which causes more channels to open.
49
this produces the rising phase of the action potential
Hodgkin cycle
50
voltage gated potassium channels that are closed at the normal resting membrane potential and respond slowly to depolarization, remain open during depolarization, close slowly when membrane potential returns to resting values
n voltage gated potassium channel
51
what is going on during the falling phase
peak was reached, h gate closed, n gate open, inhibited further movement of sodium, moving potassium out which repolarizes the membrane
52
what is going on during the recovery phase
n gates are going to remain open to undershoot the membrane resting potential
this is the refractory period
53
when the h gates of the voltage gated sodium channel are closed, the channel cannot conduct sodium no matter what the state of the m gate
refractory period
54
once an action potential occurs at one end of the neuron, the depolarization will bring the neighboring region of the cell above the threshold
regenerative depolarization
55
there are always two paths that current flowing down the inside of the axon can take
continuing down the interior of the fiber
| crossing the membrane at that point
56
the rate of voltage decrease with distance depends on
intracellular path down the axon
| resistance of the plasma membrane to current flow
57
glial cell that provides the spiral insulating material surrounding the axon
schwann cells
58
what is the insulation surrounding the axon
myelin
59
periodic breaks in the myelin sheath occur at interval of about 1mm
nodes of ranvier
60
the form of action potential conduction resulting from the jumping from one node to the next
saltatory conduction
61
two types of cells work in cardiac action potentials
pacemaker cells
| cardiac muscle cells
62
pacemaker cells resting membrane potential
-40 mV
63
where are pacemaker cells located
right atrium
64
sympathetic nervous system does what to the pacemaker cells
increases permeability, increases time to threshold, increases heart rate
65
parasympathetic does what to the pacemaker cells
decreases permeability, decrease time to threshold, decreases heart rate
66
a specialized site of contact of a neuron with another neuron or with an effector
synapse
67
signal transmission
ionotropic
68
neuronal modulation
metabotrophic
