dek pesawat dan kabin Flashcards
to make the world a better life....
Which of the following is the correct representation of the subunits of the acetylcholine (ACh) receptor at neuromuscular junction? A. Alpha Beta Gamma Delta B. Alpha2 Beta Gamma Delta C. Alpha Beta2 Gamma Delta D. Alpha Beta Gamma2 Delta E. Alpha Beta Gamma Delta2
B
Which of the following is true of the alphasubunit of the nicotinic acetylcholine receptor?
A. it contains four hydrophobic transmembrane portions
B. The binding site is not located on the alpha subunit
C. The cytoplasmic loop is themost highly conserved portion of the subunit
D. The N-Terminal is extracellular and the C-terminal is intracellular
E. The transmembrane portion is the least conserved segment
A
The number of binding sites on the nicotinic acethylcholine receptor is A.1 B.2 C.3 D.4 E.5
B
Binds GABA A. Alpha subunit of GABA a receptor B. Beta subunit of GABA a receptor C. Both D. Neither
C
Binds Benzodiazepines A. Alpha subunit of GABA a receptor B. Beta subunit of GABA a receptor C. Both D. Neither
A
Most closely linked with synaptic plasticity and cell death A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
B
GABA and this receptor are permeable to chlorid ions A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
C
Binds strychine A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
C
Binds benzodiazepine A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
A
One type of this receptor is both ligand and voltage regulated A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
B
One type of this receptor is blocked by magnesium ions A. GABA receptor B. Glutamate receptor C. Glycine receptor D. Nicotinic ACh receptor E. Serotonin (5-HT) receptor
B
Significantly permeable to calcium ions A. Kainate receptor only B. NMDA receptor only C. Quisqualate / AMPA receptor only D. A and B E. A, B, C
B
Permeable to monovalent cations A. Kainate receptor only B. NMDA receptor only C. Quisqualate / AMPA receptor only D. A and B E. A, B, C
E
Ligand gated A. Kainate receptor only B. NMDA receptor only C. Quisqualate / AMPA receptor only D. A and B E. A, B, C
E
Voltage gated A. Kainate receptor only B. NMDA receptor only C. Quisqualate / AMPA receptor only D. A and B E. A, B, C
B
Blocked by magnesium ions A. Kainate receptor only B. NMDA receptor only C. Quisqualate / AMPA receptor only D. A and B E. A, B, C
B
Which of the following is true of acetylcholine (ACh) release from the neuromuscular junction?
A. One molecule of ACh equals 10000 quanta
B. One quanta contains 10000 moleculs of ACh
C. One quanta equals one molecule of ACh.
D. One vesicle contains 10000 quanta
E. One vesicle contains 10 molecules
B
Pro-opionimelanocortin is a precursor of 1. ACTh 2. Alpha-MSH 3. Beta-Endorphin 4. Beta-lipotropin (A.123; B13; C24; D4; EAll of the above)
E
Removal of calcium ions from the cytosol in a presynaptic nerve terminal following an action potential is thought to occur by
1. Active transport
2. Binding to cytosolic proteins
3. Transport into intracellular calcium-storage vesicles
4. Reversal of flow through voltage-gated ion channels
(A.123; B13; C24; D4; EAll of the above)
A
Each of the following occurs in phototransduction EXCEPT
A. Activated rhodopsin activates a G-protein
B. Activation of cGMP phosphodiesterase increases hydrolisis of cGMP to 5’GMP
C. Current through a cGMP activated sodium channel decreases
D. Rhodopsin is activated when light converts bound 11-cis-retinal to all-trans-retinal
E. The decreased concentration of cGMP results in depolarization of the plasma membrane
E
Each of the following is true of G-proteins EXCEPT
A. Each G-protein is regulated by only one type of receptor
B. Each G-protein may regulate multiple effectors
C. The alpha subunit binds GTP
D. The Beta and gamma subunits help anchor the alpha subunit to the plasma membrane
E. The Beta and Gamma subunits modulate GDP/GTP exchange
A
D1 receptors act by this second messenger A. Calcium B. DAG C. cAMP D. cGMP E. IP3
C
Increased by nitric oxide A. Calcium B. DAG C. cAMP D. cGMP E. IP3
D
Hydrolyzed by phospholipase C A. Calcium B. DAG C. cAMP D. cGMP E. IP3
E
Synergistically activates protein kinase C with calcium A. Calcium B. DAG C. cAMP D. cGMP E. IP3
B
Binds to calmodulin A. Calcium B. DAG C. cAMP D. cGMP E. IP3
A
Photoreception utilizes this second messenger A. Calcium B. DAG C. cAMP D. cGMP E. IP3
D
Opens a calcium channel in the endoplasmic reticulum releasing free calciuminto the cytosol A. Calcium B. DAG C. cAMP D. cGMP E. IP3
E
Each of the following is true of the Na/K pump EXCEPT that it
A. Contributes to the resting potential of the cell
B. Hyperpolarizes the membrane
C. Is electrogenic
D. Transports three Na ions out for two K ions in
E. Utilizes two molecules of ATP for every three Na ions transported
E
Each of the following is true of events occurring during the action potential EXCEPT:
A. A sudden increase in conductance of Na results in depolarization
B. Chloride permeability increases during depolarization
C. During hyperpolarization the conductance of Na is lower than normal and the conductance of K is higher than normal
D. The decrease in NA permeability occuring as the action potential reaches a peak, results from inactivation of Na channels
E. The presence of voltage dependent K channels is to allow faster repolarization
B
The velocity of action potential increases with a
A. High transmembrane resistance, low internal resistance, and high membrane capacitance
B. High transmembrane resistance, low internal resistance, and low membrane capacitance
C. Low transmembrane resistance, high internal resistance, and high membrane capacitance
D. Low transmembrane resistance, low internal resistance, and high membrane capacitance
E. Low transmembrane resistance, low internal resistance, and low membrane capacitance
B
Which of the following is true of myelination?
A. It has no effect on transmembrane resistance, but increases membrane capacitance.
B. It decreases both transmembrane resistance and membrane capacitance.
C. It decreases transmembrane resistance, and increases membrane capacitance.
D. It increases transmembrane resistance and decreases membrane capacitance.
E. It increases both transmembrane resistance and membrane capacitance.
D
Usually depolarizes muscle cells past threshold A. End plate potential B. Miniature end-plate potential C. Both D. Neither
A
occurs in unstimulated cells A. End plate potential B. Miniature end-plate potential C. Both D. Neither
B
Produces a miniature end plate potential A. End plate potential B. Miniature end-plate potential C. Both D. Neither
D
Inhibitory postsynaptic potentials are produced when a transmitter opens channels permeable to A. Cl only B. Cl or K C. Na only D. Na or Cl E. Na or K
B
Which of the following is true of axonal transport?
A. Dynamin does not use ATP
B. Dynnein is the motor for anterograde fast axonal transport
C. Fast axonal transport occurs primarily along neurofilaments
D. Kinesin is the motor for retrograde fast axonal transport
E. Slow axonal transport occurs at 200-400 mm/day
A
Discharge increases with passive stretch A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
C
Discharge increases with active contraction A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
A
In series with extrafusal fibers A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
A
In parallel with extrafusal fibers A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
B
Sensitive to muscle tension A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
B
Sensitive to muscle length and velocity of length change A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
B
Innervated by group I (large myelinated) fibers A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
C
Innervated by group II (small myelinated) fibers A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
B
Conduction velocity of afferent fibers is >120 m/sec A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
D
Contains dynamic nuclear bag, static nuclear bag, and nuclear chain fibers A. Golgi tendon organ B. Muscle spindle C. Both D. Neither
B
Each of the following is true of decerebrate rigidty except
A. It results from tonic activity in the vestibulospinal and pontine reticulospinal neurons
B. It is reduced by cutting dorsal roots
C. It is reduced by destructionof the anterior lobe of the cerebellum
D. it occurs with transection between the colliculi
E. There is increased gamma motor neuron activity
C
An antidromic wave in motor fibers travelling to anterior horn cells A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
C
Has phasic and tonic components A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
F
A protective reflex involving polysynaptic reflex pathways A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
B
The electrical equivalent of the tendon reflex A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
D
The direct motor response obtained by stimulating a mixed motor-sensory nerve A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
E
A length-dependent change in muscle force when the limb is passively moved A. Clasp knife response B. Flexion reflex C. F response D. H response E. M response F. Stretch reflex
A
Contraction of the detrusor muscle of the bladder is achieved through activation of A. Parasympathetic fibers from T9 to L1 B. Parasympathetic fibers from S2 to S4 C. Sympathetic fibers from T9 to L1 D. Sympathetic fibers from S2 to S4 E. Pudendal nerves
B
Which is true of events that occur after a typical axon is severed?
A. Chromatolysis is always associated with decreased protein synthesis
B. Retraction bulbs form only at the proximal end of the cut nerve
C. Terminal degenration leads to the loss of presynaptic terminals
D. Wallerian degeneration occurs before terminal degeneration
E. Wallerian degeneration leads to loss of the proximal axon segment
C
Agents that increase the formation of CSF include 1. Carbon dioxide 2. Norepinephrine 3. Volatile anesthetic agents 4. Carbonic anhydrase inhibitors (A.123;B13;C24;D4;EAll of the above)
B
The main neurotransmitter of the Renshaw cell is thought to be A. Acetylcholine B. GABA C. Glutamate D. Glycine E. Histamine
D