PBSI 333 - Exam 1 (Principles of Neurotransmission,
Chemical Neurotransmission, Principles of
Pharmacology) Questions and Answers Latest Top
Rated 2025
Describe the Shape of Unipolar Neurons
Neuron that has a short, single stalk from the soma that splits into a T shape
What is the Role of Unipolar Neurons?
General Sensory
(Touch, Pain, Proprioception)
Think: "Uni Stalk, Sensory Talk"
Where are Unipolar Neurons found?
sensory cells from skin and organs to spinal cord
Describe the Shape of Bipolar Neurons
Has two processes: One Dendrite and One Axon on opposite ends of each other.
What is the Role of Bipolar Neurons?
Special Senses Relay
Where are Bipolar Neurons found?
Retina of the eye, Olfactory epithelium, and Vestibular/Cochlear pathways.
Why do Bipolar Neurons have this shape?
A straight input to output line keeps sensory pathways crisp and low noise for fine detail
like our speciality senses; vision, hearing, and smell.
Describe the Shape of Multipolar Neurons
Many Dendrites + One Axon (the classic starburst neuron)
What is the Role of Multipolar Neurons?
Motor Neurons and Most Interneurons
(Integration and Decision Making)
Think M (Multi, Many, Motor)
Where are Multipolar Neurons found?
CNS - Brain & Spinal Cord (Spinal Motor Neurons, Cortical Pyramidal, Purkinje)
Why do Multipolar Neurons have this shape?
Lots of dendrites = collect and integrate tons of inputs -> generate a single output down
the axon.
What is an Excitatory Neuron?
Increases firing of action potentials. Fast EPSPs - push the neuron toward firing now.
What is an EPSP? What does it do?
Excitatory Post Synaptic Potential
When a neurotransmitter opens a chemically gated ion channel that allows sodium to
enter the postsynaptic cell and DEPOLARIZES it.
What is an example of an Excitatory Neuron?
Glutamate and Acetylcholine
What is an Inhibitory Neuron?
Decreases firing of action potentials. Fast IPSPs - pull it away from firing now.
,What is an IPSP? What does it do?
Inhibitory Post Synaptic Potential
When a neurotransmitter causes the opening of a chemically gated potassium channel
on the postsynaptic cell→ postsynaptic potential. HYPERPOLARIZES
What is an example of an Inhibitory Neuron?
GABA and Glycine
What is a Modulatory Neuron?
A neuron that adjusts how other neurons and circuits respond rather than sending fast
excitatory/inhibitory signals. This makes some signals stronger, and some weaker.
How do Modulatory Neurons differ from Excitatory and Inhibitory Neurons?
Modulatory Neurons dont drive fast "yes" or "no" spikes like glutamate (excite) or GABA
(inhibit). Instead, they change how strongly circuits respond.
What are examples of Modulatory Neurons?
Dopamine and Serotonin
What are Afferent Neurons?
Neurons that carry sensory information about the external or internal environment TO
the CNS.
Sensory -> Brain/Spinal Cord
Think: "A"fferent = "A"rrives at CNS
What are Efferent Neurons?
Motor neurons which carry information away from the CNS, to the muscles/glands.
Motor Commands -> Muscles/Glands
Think: "E"fferent = "E"xits CNS
What are Interneurons?
Neurons within the brain and spinal cord that communicate internally and connect the
sensory and motor neurons
What is the function of interneurons?
To allow for integration (spinal cord and brain)
Where are the majority of proteins made?
Most proteins are made in the soma (cell body) - this is the neurons main factory.
Are dendrites and/or axons capable of producing proteins?
Dendrites can make a little locally to tweak synapses (helps learning and memory).
Axons mostly do not; they get deliveries from the soma; (Only tiny/local making during
growth or repair).
Soma = Factory
Dendrite = Fine-tuning
Axon = Delivery Route
What is Anterograde Transport?
Movement from the Soma to the Axon Terminal
What is Retrograde Transport?
Movement up the Axon toward the Soma
How fast is Retrograde Transport compare to Anterograde Transport?
Retrograde transport is 2x slower than anterograde
Why is Retrograde transport necessary?
Retrograde transport happens in order to keep the connection with the neuron alive.
, What goes through fast transport?
Enzymes, Vesicles, and Neurotransmitters.
Anything Important for activity is through fast transport.
Think: If it is important, we must transport it fast!
What goes through Slow Transport? What direction does it go in?
Slow transport is best for proteins, and it travels in only one direction.
What are Microglia?
They are the immune system cells of the CNS, acting as macrophages cleaning up
debris and pathogens.
Think: MICRO-glia, MICRO-immune system
What are the Macroglia?
Astrocytes, Oligodendrocytes, and Schwann Cells
What are Oligodendrocytes and Schwann Cells?
The two types of glial cells that form myelin sheaths around axons.
What is Myelin?
A white, fatty substance found in the myelin sheath around some nerve fibers.
What does the Myelin Sheath do?
Insulated the axon of some neurons and helps speed neural impulses
What are Astrocytes?
They are the MOST NUMEROUS GLIAL CELL, they fill spaces between neurons for
support, and regulate the composition of the extracellular space. It is important to note
that Astrocytes form a connection between neurons and capillaries. Astrocytes are
ONLY found in the brain.
They do everything except conduct action potentials.
What do Glial Cells do? What is the one thing they do NOT do?
They Support and protect neurons. They do NOT conduct action potentials.
Which glial cell produces myelination in the PNS?
Schwann Cells (1 cell myelinates 1 axon segment)
Which glial cell produces myelination in the CNS?
Oligodendrocytes (1 cell myelinates many axons)
What is Electrostatic Pressure?
Causes ions to flow towards oppositely charged areas.
Like charges repel, opposites attract - ions move to balance the charge
What is Diffusion?
The movement of particles from an area of high concentration to an area of low
concentration.
Think: DIFFusion = DIFFerence in concentration drives flow
What do diffusion and electrostatic pressure form together?
The electrochemical gradient. (Concentration and Charge forces acting at once)
We use what two main processes for ATP? What are the pros and cons for each?
Glycolysis and The Krebs Cycle
Glycolysis doesnt produce as much ATP, but it is the more efficient one. The Krebs
Cycle produces an abundant amount of ATP, however it is not as efficient and requires
a lot more.
Chemical Neurotransmission, Principles of
Pharmacology) Questions and Answers Latest Top
Rated 2025
Describe the Shape of Unipolar Neurons
Neuron that has a short, single stalk from the soma that splits into a T shape
What is the Role of Unipolar Neurons?
General Sensory
(Touch, Pain, Proprioception)
Think: "Uni Stalk, Sensory Talk"
Where are Unipolar Neurons found?
sensory cells from skin and organs to spinal cord
Describe the Shape of Bipolar Neurons
Has two processes: One Dendrite and One Axon on opposite ends of each other.
What is the Role of Bipolar Neurons?
Special Senses Relay
Where are Bipolar Neurons found?
Retina of the eye, Olfactory epithelium, and Vestibular/Cochlear pathways.
Why do Bipolar Neurons have this shape?
A straight input to output line keeps sensory pathways crisp and low noise for fine detail
like our speciality senses; vision, hearing, and smell.
Describe the Shape of Multipolar Neurons
Many Dendrites + One Axon (the classic starburst neuron)
What is the Role of Multipolar Neurons?
Motor Neurons and Most Interneurons
(Integration and Decision Making)
Think M (Multi, Many, Motor)
Where are Multipolar Neurons found?
CNS - Brain & Spinal Cord (Spinal Motor Neurons, Cortical Pyramidal, Purkinje)
Why do Multipolar Neurons have this shape?
Lots of dendrites = collect and integrate tons of inputs -> generate a single output down
the axon.
What is an Excitatory Neuron?
Increases firing of action potentials. Fast EPSPs - push the neuron toward firing now.
What is an EPSP? What does it do?
Excitatory Post Synaptic Potential
When a neurotransmitter opens a chemically gated ion channel that allows sodium to
enter the postsynaptic cell and DEPOLARIZES it.
What is an example of an Excitatory Neuron?
Glutamate and Acetylcholine
What is an Inhibitory Neuron?
Decreases firing of action potentials. Fast IPSPs - pull it away from firing now.
,What is an IPSP? What does it do?
Inhibitory Post Synaptic Potential
When a neurotransmitter causes the opening of a chemically gated potassium channel
on the postsynaptic cell→ postsynaptic potential. HYPERPOLARIZES
What is an example of an Inhibitory Neuron?
GABA and Glycine
What is a Modulatory Neuron?
A neuron that adjusts how other neurons and circuits respond rather than sending fast
excitatory/inhibitory signals. This makes some signals stronger, and some weaker.
How do Modulatory Neurons differ from Excitatory and Inhibitory Neurons?
Modulatory Neurons dont drive fast "yes" or "no" spikes like glutamate (excite) or GABA
(inhibit). Instead, they change how strongly circuits respond.
What are examples of Modulatory Neurons?
Dopamine and Serotonin
What are Afferent Neurons?
Neurons that carry sensory information about the external or internal environment TO
the CNS.
Sensory -> Brain/Spinal Cord
Think: "A"fferent = "A"rrives at CNS
What are Efferent Neurons?
Motor neurons which carry information away from the CNS, to the muscles/glands.
Motor Commands -> Muscles/Glands
Think: "E"fferent = "E"xits CNS
What are Interneurons?
Neurons within the brain and spinal cord that communicate internally and connect the
sensory and motor neurons
What is the function of interneurons?
To allow for integration (spinal cord and brain)
Where are the majority of proteins made?
Most proteins are made in the soma (cell body) - this is the neurons main factory.
Are dendrites and/or axons capable of producing proteins?
Dendrites can make a little locally to tweak synapses (helps learning and memory).
Axons mostly do not; they get deliveries from the soma; (Only tiny/local making during
growth or repair).
Soma = Factory
Dendrite = Fine-tuning
Axon = Delivery Route
What is Anterograde Transport?
Movement from the Soma to the Axon Terminal
What is Retrograde Transport?
Movement up the Axon toward the Soma
How fast is Retrograde Transport compare to Anterograde Transport?
Retrograde transport is 2x slower than anterograde
Why is Retrograde transport necessary?
Retrograde transport happens in order to keep the connection with the neuron alive.
, What goes through fast transport?
Enzymes, Vesicles, and Neurotransmitters.
Anything Important for activity is through fast transport.
Think: If it is important, we must transport it fast!
What goes through Slow Transport? What direction does it go in?
Slow transport is best for proteins, and it travels in only one direction.
What are Microglia?
They are the immune system cells of the CNS, acting as macrophages cleaning up
debris and pathogens.
Think: MICRO-glia, MICRO-immune system
What are the Macroglia?
Astrocytes, Oligodendrocytes, and Schwann Cells
What are Oligodendrocytes and Schwann Cells?
The two types of glial cells that form myelin sheaths around axons.
What is Myelin?
A white, fatty substance found in the myelin sheath around some nerve fibers.
What does the Myelin Sheath do?
Insulated the axon of some neurons and helps speed neural impulses
What are Astrocytes?
They are the MOST NUMEROUS GLIAL CELL, they fill spaces between neurons for
support, and regulate the composition of the extracellular space. It is important to note
that Astrocytes form a connection between neurons and capillaries. Astrocytes are
ONLY found in the brain.
They do everything except conduct action potentials.
What do Glial Cells do? What is the one thing they do NOT do?
They Support and protect neurons. They do NOT conduct action potentials.
Which glial cell produces myelination in the PNS?
Schwann Cells (1 cell myelinates 1 axon segment)
Which glial cell produces myelination in the CNS?
Oligodendrocytes (1 cell myelinates many axons)
What is Electrostatic Pressure?
Causes ions to flow towards oppositely charged areas.
Like charges repel, opposites attract - ions move to balance the charge
What is Diffusion?
The movement of particles from an area of high concentration to an area of low
concentration.
Think: DIFFusion = DIFFerence in concentration drives flow
What do diffusion and electrostatic pressure form together?
The electrochemical gradient. (Concentration and Charge forces acting at once)
We use what two main processes for ATP? What are the pros and cons for each?
Glycolysis and The Krebs Cycle
Glycolysis doesnt produce as much ATP, but it is the more efficient one. The Krebs
Cycle produces an abundant amount of ATP, however it is not as efficient and requires
a lot more.
