ANP 1111-THE NEURON EXAM QUESTIONS
WITH DETAILED VERIFIED ANSWERS
What do neurons do?
Neurons conduct electrical impulses from one body part to another
What are 3 special features of neurons?
Neurons have:
1) Extreme longevity: if adequately nourished can last 100 yr+
2) Amitotic
3) High metabolic rate
Neurons are ________, _________ cells
Neurons are large, complex cells
Neurons all have a ___________ + 1 or more ______________
Neurons all have a cell body + 1 or more processes
What are the 3 functional regions of the neuron?
3 functional regions of the neuron:
1) Receptive region
2) Conducting region
3) Secretory region
Describe the neuron cell body
Neuron cell body: large spherical nucleus, granular cytoplasm, extensive RER + ribosome
clusters, elaborate golgi and lots of mitochondria
What is the biosynthetic centre?
large, spherical nucleus + granular cytoplasm = biosynthetic centre
What are Nissl bodies?
,Nissl bodies are extensive RER + ribosome clusters
What is a ganglion?
A ganglion is a cluster of cell bodies in PNS
What are the 3 types of neuron processes?
Neuron processes:
1) dendrites
2) axons
3) axonal terminals
What is a tract?
Tract: bundle of nerve processes in CNS
What is a nerve?
nerve: bundle of nerve processes in PNS
Describe the anatomy of dendrites
Dendrites: short, tapering, branched extensions
How many dendrites/cell body?
usually hundreds of dendrites/cell body
Dendrites have an enormous ________ for reception from other neurons
Dendrites have an enormous SA for reception from other neurons
Dendrites conduct impulses (away/towards) cell body
Dendrites conduct impulses TOWARDS cell body
What type of potentials do dendrites create?
Dendrites create short distance, graded potentials
Describe the axon/axon terminals
, Axon + axon terminals: arises from axon hillock
How long are axons/axon terminals?
Axons/axon terminals have variable length (can be > 1 metre)
The rate of conduction in an axon increases with what?
The rate of conduction in an axon increases with axon diameter
How many axon/neuron?
Usually 1 axon/neuron, but branches at end
How many terminal branches at the end of an axon?
~10,000 terminal branches
Terminal branches end with what?
Terminal branches end knob-like axonal terminals
What do neurotransmitters do?
Neurotransmitters convey information from one axon to the next
In terms of organelles, how do axons and cell bodies differ?
Axon has same organelles as cell body, but no Nissl bodies
How durable are axons if they are cut?
Axons quickly degenerate if cut
Axons have elaborate _____________
Axons have elaborate CYTOSKELETONS
Elaborate cytoskeleton in axon moves material to & fro in which 2 directions?
Elaborate cytoskeleton in axon moves material to & fro in anterograde and retrograde
What moves in anterograde?
anterograde: mitochondria, cytoskeletal elements, NTs
WITH DETAILED VERIFIED ANSWERS
What do neurons do?
Neurons conduct electrical impulses from one body part to another
What are 3 special features of neurons?
Neurons have:
1) Extreme longevity: if adequately nourished can last 100 yr+
2) Amitotic
3) High metabolic rate
Neurons are ________, _________ cells
Neurons are large, complex cells
Neurons all have a ___________ + 1 or more ______________
Neurons all have a cell body + 1 or more processes
What are the 3 functional regions of the neuron?
3 functional regions of the neuron:
1) Receptive region
2) Conducting region
3) Secretory region
Describe the neuron cell body
Neuron cell body: large spherical nucleus, granular cytoplasm, extensive RER + ribosome
clusters, elaborate golgi and lots of mitochondria
What is the biosynthetic centre?
large, spherical nucleus + granular cytoplasm = biosynthetic centre
What are Nissl bodies?
,Nissl bodies are extensive RER + ribosome clusters
What is a ganglion?
A ganglion is a cluster of cell bodies in PNS
What are the 3 types of neuron processes?
Neuron processes:
1) dendrites
2) axons
3) axonal terminals
What is a tract?
Tract: bundle of nerve processes in CNS
What is a nerve?
nerve: bundle of nerve processes in PNS
Describe the anatomy of dendrites
Dendrites: short, tapering, branched extensions
How many dendrites/cell body?
usually hundreds of dendrites/cell body
Dendrites have an enormous ________ for reception from other neurons
Dendrites have an enormous SA for reception from other neurons
Dendrites conduct impulses (away/towards) cell body
Dendrites conduct impulses TOWARDS cell body
What type of potentials do dendrites create?
Dendrites create short distance, graded potentials
Describe the axon/axon terminals
, Axon + axon terminals: arises from axon hillock
How long are axons/axon terminals?
Axons/axon terminals have variable length (can be > 1 metre)
The rate of conduction in an axon increases with what?
The rate of conduction in an axon increases with axon diameter
How many axon/neuron?
Usually 1 axon/neuron, but branches at end
How many terminal branches at the end of an axon?
~10,000 terminal branches
Terminal branches end with what?
Terminal branches end knob-like axonal terminals
What do neurotransmitters do?
Neurotransmitters convey information from one axon to the next
In terms of organelles, how do axons and cell bodies differ?
Axon has same organelles as cell body, but no Nissl bodies
How durable are axons if they are cut?
Axons quickly degenerate if cut
Axons have elaborate _____________
Axons have elaborate CYTOSKELETONS
Elaborate cytoskeleton in axon moves material to & fro in which 2 directions?
Elaborate cytoskeleton in axon moves material to & fro in anterograde and retrograde
What moves in anterograde?
anterograde: mitochondria, cytoskeletal elements, NTs
