Lecture 4 (anatomy, cells, resting potential) Flashcards
What are the 3 main parts of the neuron?
- Soma
- Axon
- Terminal
What are the parts of the soma and its function?
- dendrites (receive electrochemical signals)
- spines (^^)
- receptors (on the ends of D&S)
What are the parts of the axon and its function?
- axon hillock
- myelin
- nodes of ranvier
Electrochemical signals move across the axon into the terminal
What are the parts of the terminal and its function?
- Vesicles
- NTs
The ec signal reaches the terminal, then moves through the membrane to the synapse to bind to the next neuron
3 types of glial cells?
- astroglial cells
- oligodendroglial cells
- microglial cells
Astroglial cells –> job? how?
Job: form and maintain the blood brain barrier
How: surrounds blood vessels in the brain, plugs/patches holes
Why is the blood brain barrier important?
Prevents bad things (bacteria, etc.) from getting into the brain. They stay in the blood vessels to get filtered out by the kidneys/liver
Oligodendroglial cells –> job? how?
Job: form and maintain the myelin layer/sheath around the axons of neurons
How: they wrap around, coating the axon
Why is myelin important?
- insulating layer
- Facilitates quicker transmission/communication between neurons
- allows electrical impulses to transmit quickly
- it is interrupted at the nodes of ranvier
Microglial cells –> job? how?
Job: ‘immune system’ or ‘cleaners’ of the brain
eliminate foreign substances OUTSIDE of
neurons (floating in the brain)
How: they form macrophages
Phagocytosis: a cell ingests or engulfs other cells, particles, or bacteria to dispose of them
Why are microglial / macrophages important?
Central role in protecting against infection in the brain
3 states of a neuron:
- Resting
- Excited
- Inhibited
Define propagation:
the movement of signals between neurons
Define resting potential
Electrical charge of the cell when it’s doing nothing
What is the charge? Characteristics of RP?
-70mV
- unequal distribution of ions inside and outside
- inside is MORE NEGATIVE than outside