1
Q
Ca2+ entering voltage gated channels in the presynaptic neuron causes what during muscle neurotransmission
A
- acetylcholine release and binding to receptor
2
Q
what happens in an excitatory response
A
- Vm depolarizes
- increases probability of firing an action potential
3
Q
what kind of gap occurs between cells in electrical synapses
A
- narrow gap
4
Q
chemical synapse between neuron and non-neural effector cell is called
A
- neuroeffector junction
5
Q
spatial summation
A
- from different regions of the cell that collide and can be added together
6
Q
two types of graded responses
A
- excitatory
- inhibitory
7
Q
site of initiation on axon of action potential
A
- first node of Ranvier
- axon hillock
8
Q
electrical synapses occurs between
A
- neuron
- another cell
9
Q
how does Ca2+ get back into the intracellular organelle?
A
- SERCA pumps
10
Q
what is the principle route of Ca2+ removal from cytosol
A
- SERCA pump
12
Q
inhibitory graded response called
A
- inhibitory post synaptic potential (IPSP)
13
Q
when graded potentials exceed threshold
A
- an action potential is generated
15
Q
most common name for synapse between two neurons
A
- neuronal synapse
16
Q
local current between depolarized end plate and adjacent muscle plasma membrane causes
A
- muscle fiber action potential initiation
- propagated action potential in muscle plasma membrane
17
Q
graded potentials at the NMJ
A
- always excitatory
18
Q
loops in connexons
A
- cytoplasmic
- extracellular
18
Q
what happens after action potential arrives at presynaptic terminal
A
- voltage gated Ca2+ channels open and Ca2+ enters the cell
19
Q
how Ca2+ ATPase works
A
- brings H+ into cytosol
- pumps Ca2+ out into ECF
20
Q
what activates post synaptic cell
A
- bound neurotransmitters
21
Q
what happens to concentrations of Na+/K+ and Ca2+ if NA+/K+ ATPase is poisoned
A
- intracellular K+ will decrease
- cytosolic Ca2+ will increase
- intracellular Na+ will increase
- you won’t be able to pump K+ into the cell or Na+ out of the cell
- buildup of Na+ in the cell via it’s concentration gradient will allow you to shunt Ca2+ out into cytosol
22
Q
whether the post synaptic response is IPSP or EPSP is determined by
A
- neurotransmitter released
- receptor at post-synaptic cell
- whether ion channels open or close
24
Q
what is present in the membrane of each cell of gap junctions in electric synapse
A
- connexons
25
Q
size of gap junction in electrical synapse
A
- 3.5 nm
26
Q
what determines whether ion channels open or close
A
- selectivity properties of channels
- ions present and their gradients across the membrane
27
where does the action potential arrive at start of synaptic transmission
- presynaptic terminal
28
which type of synapse is most common in the nervous system?
- chemical
30
EPSPs action on membrane potential
- move membrane potential toward threshold for action potential
31
voltage gated sodium channels are located where in neuromuscular junction
- bottoms of junctional folds
| - longitudinal surfaces
32
types of summation in graded potentials
- spatial summation
| - temporal summation
33
cytoplasmic loops in connexons important for
- regulation
35
what calcium channels are there in the plasma membrane?
- voltage gated
- ligand gated
- Ca2+ gated
36
ACh receptors are located where in neuromuscular junction
- top of junctional folds of sarcolemma
37
where does additional Ca2+ come from mainly
- voltage-gated Ca2+ channels
38
pre synaptic features
- axon swelling
- synaptic vesicles
- mitochondria
- pre-synaptic density
40
extracellular loops in connexons important for
- hemophilic interactions
42
site of initiation on axon of graded potential
- post synaptic membrane
43
organelles that store Ca2+
- SER
- ER
- mitochondria
44
a rise in intracellular Ca2+ triggers what
- fusion of synaptic vesicle with presynaptic membrane
45
what happens in an inhibitory response
- Vm hyper polarizes or stabilizes
| - decrease probably of firing an action potential
46
cytosolic free Ca2+ can bind to
- calcium-binding proteins
- protein kinases
- other proteins to mediate cell's response
47
chemical synapses can occur between
- two neurons
| - a neuron and a non-neuronal effector
47
synaptic cleft size between two neurons
- 25 nm
49
fate of neurotransmitter after activation of post synaptic cell
- breaks down
- taken up by presynaptic terminal
- diffuse away from synapse
50
what are connexons formed by
- 6 connexins
52
can action potentials summate?
- no!
53
gap junctions allow for
- rapid communication between linked cells
53
synapses between neurons can occur where?
- on the cell body (axosomatic)
- axons (axo-axonal)
- dendrites (axodendritic)
54
ways calcium enters cytosol
- through channel
| - through intracellular stores of Ca2+ within organelles
55
graded potentials and distance
- decays over distance
56
cytosolic calcium levels compared to extracellular concentrations
- very low
| - so calcium enters cytosol
57
synaptic cleft composed of
- glycocalyx
58
changes in permeability evoke what kind of response
- graded response
59
electron density in post synaptic cell located
- adjacent to synaptic cleft
60
how CA2+/Na+ exchanger works
- brings Na+ into cytosol
| - pumps Ca2+ out into ECF
61
temporal summation
- from same neuron over different time to build on amplitude of response
62
what kind of junctions occur within the electrical synapse
what does it do?
- gap junction
| - link cells
62
chemical synapse between neuron and skeletal muscle is called
- neuromuscular junction
63
how does Ca2+ get back out of the cell?
- Ca2+/Na+ exchanger in plasma membrane
| - plasma membrane Ca2+ ATPase
64
two types of synapses
- electrical
| - chemical
65
how SERCA pump works
- brings H+ into cytosol
| - pumps Ca2+ back into organelle
66
neurotransmitter molecules are synthesized and packaged in what
- vesicles
66
acetylcholine release and binding to receptor causes what during muscle neurotransmission
- Na+ entry
- local current between depolarized end plate and adjacent muscle plasma membrane
-
67
what type of receptor is an acetylcholine receptor
- nicotinic cholinergic receptor
68
where do neurotransmitter molecules go
- diffuse across synaptic cleft
| - bind to specific receptors on post synaptic cell
68
what neurotransmitter is always at the neuromuscular junction
- acetylcholine
68
what happens to acetylcholine at end of muscle neurotransmission?
- degraded by acetylcholinesterase
69
what can pass between cells in gap junctions in electrical synapse
- ions, sugars, solutes
69
excitatory graded response called
- as NMJ
- excitatory post synaptic potential (EPSP)
| - end plate potential (EPP)
71
graded potentials are ____ changes in membrane potential
- transient changes in membrane potential
71
IPSPs action on membrane potential
- stabilize or move membrane potential away from threshold for an action potential
72
start of pre-synaptic events during neurotransmission with motor cell
- motor neuron action potential
| - Ca2+ enters voltage gated channels
72
binding of a neurotransmitter to its receptor results in
- ion permeability changes in post synaptic cell
Cardio Exam 1
flashcards
Decks in class (25)
# Cards
-
Intro to Anatomy24
-
Intro to Embryology88
-
Cardiac Imaging46
-
Anterior Thoracic Wall Anatomy101
-
Heart Anatomy46
-
Basic Concepts in Physiology54
-
Neuronal Action Potentials39
-
Synaptic Transmission72
-
Skeletal and Smooth Muscle78
-
Cardiac Muscle - Quiz 173
-
ANS Anatomy112
-
ANS Pharmacology39
-
The Cardiac Cycle25
-
Neurotransmitters92
-
Autonomic Regulation of the Heart - Quiz 135
-
EKG - Quiz 125
-
Histology44
-
ANS Anatomy Jensen Lecture20
-
Clinical EKG36
-
Condensed Anatomy16
-
Tachyarrhythmias - Quiz 2 - SPEND MORE TIME ON THIS58
-
Practice EKG slides35
-
Mechanism of Arrythmias - Quiz 279
-
Antiarrhythmic Drugs - Quiz 263
-
Antiarrhythmic Drugs Pictures3
