SPLH 620 Exam 1 Latest Update 2025
Questions and Verified Solutions Graded
A+|Assured Success
What are the different membrane refractory periods? - CORRECT ANSWER-1. Absolute:
~1 msec (during impulse)
- an action potential cannot be
generated during the absolute
refractory period
2. Relative: an action potential can be generated
,Where do AP's typically originate at and why? - CORRECT ANSWER-1. Axon hillock (has a
lower threshold than the rest of the plasma membrane)
•AP only changes voltage on the surface near the membrane... -not within the whole cell
What is Saltatory Conduction? - CORRECT ANSWER-how the AP's are propagated down
the axon (they jump from each Node of Ranvier to the next).
---AP depolarizes each successive patch of membrane
• Slows down transmission in nonmyelinated axons
- In myelinated axons,...
• the only membrane that is exposed is at the nodes.
- AP jumps from node to node only depolarizing membrane at
node
- Voltage sensitive Na+ channels are concentrated in these areas
What are the 2 factors that determine conduction velocity? - CORRECT ANSWER-1.
Myelin
2. Diameter of axon
---fastest (large diameter, myelinated)
---lowest (small diameter, unmyelinated).
,What are the three fundamental elements of synaptic transmission? - CORRECT
ANSWER-1. Presynaptic neuron (axon terminal) neurotransmitters are released
2. Synaptic cleft
3. Postsynaptic neuron (dendrite) receptor where the neurotransmitter binds
What kind of jobs does the nervous system perform? - CORRECT ANSWER-1. Controls
body functions
2. Transmits information
3. Receives sensory input from internal and external environments
What are the two approaches to the mind-body problem? - CORRECT ANSWER-1.
Dualism
-Mind and body are separate
»mind is a uniquely human attribute that is
not constrained by physical laws
2. Monism
-Mind is a property of a physical nervous system
What are the major divisions of the nervous system? - CORRECT ANSWER-NS to 1) CNS
(brain & spinal cord)
, NS to 2) PNS (somatic NS with afferent and efferent nerves) (Autonomic NS with afferent and
efferent nerves)
What are the 4 directional and the 2 locational in the brain. - CORRECT ANSWER-1.
Anterior (rostral)
2. Posterior (caudal)
3. Ventral (inferior)
4. Dorsal (superior)
1. Ipsilateral
2. Contralateral
What are the 3 anatomical planes of the CNS? - CORRECT ANSWER-1. Sagittal (divides
brain into left and right).
2. Coronal/frontal (divides brain into anterior and posterior).
3. Axial/transverse (divides brain into upper and lower)
What are the 2 basic cell types in the CNS? - CORRECT ANSWER-1. Neurons (information
carriers)
2. Glia (support cells)
What do Neuroglia provide and what are the 3 main types? - CORRECT ANSWER-
Physical support, nutrient flow, nerve "housekeeping"
Questions and Verified Solutions Graded
A+|Assured Success
What are the different membrane refractory periods? - CORRECT ANSWER-1. Absolute:
~1 msec (during impulse)
- an action potential cannot be
generated during the absolute
refractory period
2. Relative: an action potential can be generated
,Where do AP's typically originate at and why? - CORRECT ANSWER-1. Axon hillock (has a
lower threshold than the rest of the plasma membrane)
•AP only changes voltage on the surface near the membrane... -not within the whole cell
What is Saltatory Conduction? - CORRECT ANSWER-how the AP's are propagated down
the axon (they jump from each Node of Ranvier to the next).
---AP depolarizes each successive patch of membrane
• Slows down transmission in nonmyelinated axons
- In myelinated axons,...
• the only membrane that is exposed is at the nodes.
- AP jumps from node to node only depolarizing membrane at
node
- Voltage sensitive Na+ channels are concentrated in these areas
What are the 2 factors that determine conduction velocity? - CORRECT ANSWER-1.
Myelin
2. Diameter of axon
---fastest (large diameter, myelinated)
---lowest (small diameter, unmyelinated).
,What are the three fundamental elements of synaptic transmission? - CORRECT
ANSWER-1. Presynaptic neuron (axon terminal) neurotransmitters are released
2. Synaptic cleft
3. Postsynaptic neuron (dendrite) receptor where the neurotransmitter binds
What kind of jobs does the nervous system perform? - CORRECT ANSWER-1. Controls
body functions
2. Transmits information
3. Receives sensory input from internal and external environments
What are the two approaches to the mind-body problem? - CORRECT ANSWER-1.
Dualism
-Mind and body are separate
»mind is a uniquely human attribute that is
not constrained by physical laws
2. Monism
-Mind is a property of a physical nervous system
What are the major divisions of the nervous system? - CORRECT ANSWER-NS to 1) CNS
(brain & spinal cord)
, NS to 2) PNS (somatic NS with afferent and efferent nerves) (Autonomic NS with afferent and
efferent nerves)
What are the 4 directional and the 2 locational in the brain. - CORRECT ANSWER-1.
Anterior (rostral)
2. Posterior (caudal)
3. Ventral (inferior)
4. Dorsal (superior)
1. Ipsilateral
2. Contralateral
What are the 3 anatomical planes of the CNS? - CORRECT ANSWER-1. Sagittal (divides
brain into left and right).
2. Coronal/frontal (divides brain into anterior and posterior).
3. Axial/transverse (divides brain into upper and lower)
What are the 2 basic cell types in the CNS? - CORRECT ANSWER-1. Neurons (information
carriers)
2. Glia (support cells)
What do Neuroglia provide and what are the 3 main types? - CORRECT ANSWER-
Physical support, nutrient flow, nerve "housekeeping"
