CDIS 421 Neuroscience of Communication (Ch.
1-7) Exam
What are the fundamental activities of a neuron? - ANSWER Receiving input - from
dendrites + soma, categorizing inputs into excitatory or inhibitory
Integrating input - axon hillock generates the overall change in baseline electrical state
of neuron —> determines if action potential can be created
Form an output - signal transmitted across axon to the synapse.
What are bipolar neurons? - ANSWER one axon and one dendrite
- found in retinal ganglion cells
What are pseudounipolar neurons? - ANSWER - One axon and one single primary
dendrite that attach to the cell body at the same point
- Found in afferent system of spinal/trigeminal nerves.
What are multipolar neurons? - ANSWER 1 axon and several dendrites
Most abundant
Motor neurons and interneurons
What is the difference between neurons and glial cells? - ANSWER neurons: generate
and transmit nerve impulses; may be inhibitory or excitatory
glial cells: provide supportive functions to neurons
What are the two functional groups of glial cells? - ANSWER microglia, macroglia
,What are microglia? - ANSWER "sanitation workers" of the brain, part of immune sytem,
recruited to sites of injury or infection and function as phagocytes to get rid of debris
and dead tissue
What are the types of macroglia? - ANSWER astrocytes, oligodendrocytes, schwann
cells
What are similarities and differences between oligodendrocytes and Schwann cells? -
ANSWER They both produce myelin for axons, but oligodenrocytes produce them for the
CNS and Schwann cells produce them for the PNS.
What are astrocytes? - ANSWER The most numerous type of glial cells and are most
complex
- They regulate K+ concentration and glutamate in extracellular space.
- They create the blood-brain barrier (BBB)
What is the blood-brain barrier? - ANSWER a filtering mechanism of the capillaries that
carry blood to the brain and spinal cord tissue, blocking the passage of certain
substances.
- astrocytes are directly involved in this!
What are electrical synapses? - ANSWER Gap junction between 2 nerve cells that
require extremely rapid signal transmission (retina, olfactory bulb, cortex, etc).
- Pre-synaptic and postsynaptic membranes are extremely close to each other.
- Received ions flow trough gap junction channels
- Less vulnerable to fatigue
- Signal transmission is multi-directional
What are chemical synapses? - ANSWER Synaptic cleft where impulses are slowly
transmitted in one direction by neurotransmitters
, - Neurotransmitters are received by chemical receptors on post-synaptic membrane
- Vulnerable to fatigue
- Most abundant in the nervous system
- Flexible and adaptive in structure and function
What are 3 types of ion channels? - ANSWER voltage gated, ligand gated, mechanically
gated
What are ligand gated channels? - ANSWER Ligand binds to channel, causing a change
in its shape, opening the channel
What are voltage gated channels? - ANSWER channels that open and close in response
to changes in membrane potential
What are mechanically gated channels? - ANSWER open and close in response to
physical deformation of receptors
What is neural integration? - ANSWER the process by which incoming inhibitory and
excitatory postsynaptic potentials summate at the axon hillock and determine if the net
change in electric potential of the neuron can cross the firing threshold of the axon
hillock.
What is the difference between gray and white matter? - ANSWER Gray matter - Lacks
myelin; it contains mostly cell bodies of motor neurons and interneurons.
White matter - Large amounts of myelinated axons.
What is white matter called in the PNS vs. CNS? - ANSWER PNS - nerves
CNS - bundles of axons (tracts, fibers, pathways, peduncles, fasciculi, leminscus,
capsule, commissure
1-7) Exam
What are the fundamental activities of a neuron? - ANSWER Receiving input - from
dendrites + soma, categorizing inputs into excitatory or inhibitory
Integrating input - axon hillock generates the overall change in baseline electrical state
of neuron —> determines if action potential can be created
Form an output - signal transmitted across axon to the synapse.
What are bipolar neurons? - ANSWER one axon and one dendrite
- found in retinal ganglion cells
What are pseudounipolar neurons? - ANSWER - One axon and one single primary
dendrite that attach to the cell body at the same point
- Found in afferent system of spinal/trigeminal nerves.
What are multipolar neurons? - ANSWER 1 axon and several dendrites
Most abundant
Motor neurons and interneurons
What is the difference between neurons and glial cells? - ANSWER neurons: generate
and transmit nerve impulses; may be inhibitory or excitatory
glial cells: provide supportive functions to neurons
What are the two functional groups of glial cells? - ANSWER microglia, macroglia
,What are microglia? - ANSWER "sanitation workers" of the brain, part of immune sytem,
recruited to sites of injury or infection and function as phagocytes to get rid of debris
and dead tissue
What are the types of macroglia? - ANSWER astrocytes, oligodendrocytes, schwann
cells
What are similarities and differences between oligodendrocytes and Schwann cells? -
ANSWER They both produce myelin for axons, but oligodenrocytes produce them for the
CNS and Schwann cells produce them for the PNS.
What are astrocytes? - ANSWER The most numerous type of glial cells and are most
complex
- They regulate K+ concentration and glutamate in extracellular space.
- They create the blood-brain barrier (BBB)
What is the blood-brain barrier? - ANSWER a filtering mechanism of the capillaries that
carry blood to the brain and spinal cord tissue, blocking the passage of certain
substances.
- astrocytes are directly involved in this!
What are electrical synapses? - ANSWER Gap junction between 2 nerve cells that
require extremely rapid signal transmission (retina, olfactory bulb, cortex, etc).
- Pre-synaptic and postsynaptic membranes are extremely close to each other.
- Received ions flow trough gap junction channels
- Less vulnerable to fatigue
- Signal transmission is multi-directional
What are chemical synapses? - ANSWER Synaptic cleft where impulses are slowly
transmitted in one direction by neurotransmitters
, - Neurotransmitters are received by chemical receptors on post-synaptic membrane
- Vulnerable to fatigue
- Most abundant in the nervous system
- Flexible and adaptive in structure and function
What are 3 types of ion channels? - ANSWER voltage gated, ligand gated, mechanically
gated
What are ligand gated channels? - ANSWER Ligand binds to channel, causing a change
in its shape, opening the channel
What are voltage gated channels? - ANSWER channels that open and close in response
to changes in membrane potential
What are mechanically gated channels? - ANSWER open and close in response to
physical deformation of receptors
What is neural integration? - ANSWER the process by which incoming inhibitory and
excitatory postsynaptic potentials summate at the axon hillock and determine if the net
change in electric potential of the neuron can cross the firing threshold of the axon
hillock.
What is the difference between gray and white matter? - ANSWER Gray matter - Lacks
myelin; it contains mostly cell bodies of motor neurons and interneurons.
White matter - Large amounts of myelinated axons.
What is white matter called in the PNS vs. CNS? - ANSWER PNS - nerves
CNS - bundles of axons (tracts, fibers, pathways, peduncles, fasciculi, leminscus,
capsule, commissure
