Bms 333 Exam 2 Neuro
- 1.Which of the following best describes a neuron at the resting state?
- A.
Na+-K+ ATPase pumps are not active
- B.
The resting membrane potential is about +65 mV
- C.
K+ ions leak out of a neuron via nongated K+ channels
- D.
Voltage-gated K+ channels are open
- E.
The resting state represents the relative refractory period
- 2.A local anesthetics, lidocane, prevents generation of action potential by inactivating:
- A.
Receptors for gamma aminobutylic acid (GABA)
- B.
Nongated Na+ channels
- C.
Voltage-gated Ca++ channels
- D.
Voltage-gated Na+ channels
- E.
Release of neurotransmitter Ach
- 3.Astrocytes:
- A.
Form choroid plexus that produce cerebrospinal fluid
- B.
Transport glucose from capillaries to neurons
- C.
Give rise to perivascular end feet in the dorsal root ganglion
- D.
Stop dividing shortly after birth
- E.
Promote intercellular accumulation of neurotransmitter glutamate
- 4.A lesion of the lateral funiculus is likely to affect:
- A.
Central canal
- B.
Neuronal perikarya
- C.
Ependymal cells
- D.
Schwann cells
- E.
Oligodendrocytes
- 5.When an excitatory synapse 'A' and inhibitory synapse 'B' are stimulated simultaneously, the postsynaptic neuron is likely to generate:
- A.
An excitatory postsynaptic potential only
- B.
An inhibitory poststynaptic potential only
- C.
No obvious overall changes in membrane potential
- D.
Hyperpolarizing potential
- E.
An action potential
- 6.What do you expect to see in a dog with a large lesion affecting the intermediate substance of teh spinal cord?
- A.
Presence of quadriceps reflex
- B.
Absence of quadriceps reflex
- 7.Demyelination of axon is likely to result in:
- A.
Slight increase in conduction velocity of action potential
- B.
Decreased conduction velocity to the speed typically seen in nonmyelinated nerve fibers
- C.
A loss of conduction of action potentials as local currents cannot reach the voltage-gated Na+ and K+ channels
- D.
Increased conduction velocity due to a loss of resistance imposed by axonal plasma membrane
- E.
No apparent change in conduction speed as voltage-gated Na+ and K+ channels are still available in the demyelinated area
- 8.Which of the following is affected in a dog with tic paralysis?
- A.
Sensory neurons in the dorsal horn
- B.
Postsynaptic acetycholine receptors
- C.
Release of Ach at the neuromuscular junction
- D.
Release of glycine from the pre-synaptic site
- E.
Motor neurons in the ventral horn
- 9.Which statement is true about the neuromuscular synapse?
- A.
Nerve fibers that form the neuromuscular synapse leave the spinal cord via the dorsal root
- B.
Terminal branches of the motor end plate release glutamate
- C.
Neuromuscular synapse is affected by myasthenia gravis
- D.
Postsynaptic membrane has receptors for gamma aminobutylic acid (GABA)
- E.
Axon terminals are covered with astrocytes
- 10.The pointed portion (depolarization) of an action potential is triggered by:
- A.
Inhibitory postsynaptic potentials
- B.
Na+-K+ ATPase pumps
- C.
Opening of voltage-gated K+ channels
- D.
Inactivation of voltage-gated Na+ channels
- E.
Activation of voltage-gated Na+ channels
- 11.Which neurotransmitter generates excitatory postsynaptic potential (EPSP) that depolarizes the postsynaptic membrane during synaptic transmission?
- A.
Glycine
- B.
Ach
- C.
GABA
- D.
All of the above
- 12.A nerve fiber is:
- A.
Made of an axon and endoneurium
- B.
Made of an axon and Schwann cells
- C.
Made of a myelinated axon and endoneurium
- D.
Made of a nerve fasicle surrounded by perineurium
- E.
Made of an axon and oligodendrocytes
- 13.For inhibitory graded potential (IPSP) to occur during synaptic transmission, an inhibitory neurotransmitter must bind to the:
- A.
Ligand-gated receptors to trigger influx of Cl-
- B.
Ligand-gated receptors to trigger influx of Na+
- C.
Voltage-gated Na+ channels to trigger influx of Na+
- D.
Voltage-gated K+ channels to trigger influx of K+
Related Topics
Recent Quizzes
Featured Quizzes
Back to top