4.1 HY The cells of the Nervous System Flashcards
What’s the difference between the axon and the dendrites in relation to the soma?
The axons carry neural signals away from the soma; dendrite carry signals towards the stroma.
What does the axon hillock do?
- integrates incoming signals.
- Places an an important role in action potentials. If there are enough stimuli, it will make the action potential happen
What is the role of myelin?
What disease targets myelin sheaths?
It’s a fatty membrane that prevents signal loss or crossing signals. Like rubber coated wires prevent cross wires from coming intact with one and other.
Multiple sclerosis targets myelin sheaths in the CNS (attacks oligodendrocytes)
What two cells produce myelin?
Central Nervous system: oligodendrocytes
Peripheral Nervous System: Schwann cells.
Mnemonic: COPS= central oligo peripheral Schwann
What is the synapse?
What is the synaptic cleft?
The synapse is where the nerve terminal, synaptic cleft, and post synaptic membrane come together.
The synaptic cleft is the area between where two neurons meet.
How can nerves be broadly classified? (x3)
Sensory, motor, or mixed
What are tracts and nucli?
Tracks: anxons that are bundled together, only carry one type of information.
Nuclei: Cell bodies of neurons in the same tract.
What are five types of glial cells or neuroglia?
What, in general, do glial cells do?
Glial cells play both structural and supportive roles for the neurons.
1. Astrocytes.
2. Ependymal Cells
3. Microglia
4. Oligodendrocytes
5. Schwann Cells
AEMOS
What do the astrocytes do?
Nourish neurons and form the blood-brain barrier, which controls the transmission of solutes from the bloodstream into the nervous tissue.
What do the Ependymal Cells do?
They line the ventricles of the brain and produce cerebral spinal fluid, which physically supports the brain and serves as a shock absorber.
What do microglia do?
They are phagocytic cells that ingest and break down waste products and pathogens in the central nervous system.
What do oligodendrocytes and Schwann cells do?
They produce myelin around the axons.
The oligodendrocytes work in the central nervous system.
The Schwann cells work in the peripheral nervous system.
What two types of glial cells, if not properly functioning, will make an individual most susceptible to a CNS infection?
Astrocytes + Microglia
Astrocytes nourish neurons and form the blood brain barrier, which helps protect the brain from foreign pathogens gaining entrance.
Microglia ingest and breakdown waste products and pathogens.
What type of cell is being targeted in GBS, Guillain-Barre syndrome, an autoimmune disease that causes demyelination in the peripheral nervous system?
Schwann cells, because they are active in the PNS
What is a collection of cell bodies called in the CNS? In the PNS?
Nucleus- collection of cell bodies in the central nervous system
Ganglion- collection of cell bodies in the peripheral nervous system.
