Lesson 4 (Unit 1) Flashcards
What does the Central Nervous System (CNS) consist of?
The brain and spine.
What does the Peripheral Nervous System (PNS) consist of?
The peripheral nerves.
What are the two functional branches of the nervous system?
- Somatic nervous system
- Autonomic nervous system
What is the function of the somatic nervous system?
Involved in voluntary movement and conscious perception.
What is the function of the autonomic nervous system?
Involved with involuntary control of different internal organs and glands.
Where is gray matter found?
At the outer cortex of the brain and inner region of the spinal cord.
Where is white matter found?
In the inner region of the brain and outer region of the spinal cord.
What is the definition of a nucleus in the nervous system?
A clump/collection of cell bodies or neurons in the Central Nervous System with their own functions.
What is the definition of a ganglion?
A collection of cell bodies in the peripheral nervous system.
What are the three main structures of a neuron?
- Soma/cell body
- Dendrites
- Axons
What is the major function of neurons?
Communication: receiving messages from other neurons and sending messages to other neurons.
What is myelin?
A sheath or insulating layer that forms around nerves.
What is the function of myelin?
Allows for electrical impulses to transmit quickly and efficiently along the nerve cells.
List the four glial cells in the CNS
- Astrocytes
- Oligodendrocytes
- Microglia cells
- Ependymal cells
What is the function of Astrocytes of the CNS?
Create the blood-brain barrier
What is the function of Oligodendrocytes of the CNS?
Make Myelin
What is the function of microglial Cells of the CNS?
They find and breakdown germs
What is the function of Ependymal Cells of the CNS?
Secrete Cerebral spinal fluid
List the two glial cells in the PNS and their functions.
- Satellite cells
- Schwann cells
What is the function of Satellite Cells of the PNS?
They aid in general supportive functions
What is the function of Schwann Cells of the PNS?
Make/produce myelin
How do axons with myelin differ from axons without myelin?
Axons with myelin can send electrical impulses faster in comparison to axons without myelin.
What do ligand-gated channels require to open?
The binding of a neurotransmitter.
What do mechanically gated channels require to open?
A mechanical change.
What do voltage-gated channels require to open or close?
A change in charge.
What is the resting membrane potential for a cell?
-70 mV.
What occurs at -55 mV during an action potential?
It reaches threshold and an action potential will occur.
What happens during depolarization?
The cell becomes more positive.
What happens during repolarization?
The cell goes back to negative.
What is hyperpolarization?
The cell becomes even more negative.
What is a synapse?
The connection between a neuron and its target cell.
What is propagation in the context of neurons?
The communication between a neuron and target cell.
What is the refractory period?
The period during which the cell cannot be stimulated for another action potential.
