Neurons (2 Part 2) Flashcards
Receptors
Specialised neural components that respond to specific kinds of energy
Soma
The cell body of a neuron , which contains the nucleus
What is myelin made by**
Glial cells
Glial cells*
A type of support cell in the CNS and PNS that forms myelin sheaths
What does the myelin sheath do?
Prevents messages/ signals from ‘spreading’ between adjacent neurons
What do nodes of ranvier do
Help to speed up conduction
Recording neural signals set up:
Recoding electrode inside the nerve fibre
REFERENCE electrode outside the fibre
(Difference in charge between = -70mV
Sodium ions .. positive/ electric charge (Na)
Positive
Chlorine ions.. positive/ negative charge
Negative
Potassium ions .. positive/ negative charge
Positive
which ions are contained in the physiological solution that surround neurons
Sodium, potassium, chlorine
what do special proteins pump in/out of the membrane surrounding neurons?**
Pump out 3 sodium (Na) and take in 2 potassium (K) (-> inside negative charge -> -70mV)
How is an action potential generated*
Split-second changes in the movement of ions across the cell membrane
Hyperpolarisation*
When the potential of a neuron goes below -70mV immediately following the action potential
What are the pores in the membrane called that surround neurons
Channels
What are action potentials essential for?
Sending rapid communications between the brain and body
When do action potentials occur?*
When the permeability of the membrane changes (Na flows IN - more postitive ; K flows out - more negative)
Upper firing rate of action potentials
500-800 impulses per second
Acetylecholine NT function
Regulates motor control
Attention, learning, memory, sleeping and dreaming
Dopamine NT function
Movement, motivation, emotional pleasure and arousal
Glutamate NT function
Excitatory NT involved in learning and memory
Gamma-aminobutyric acid (GABA) NT function
Primary inhibitory NT
Seratonin NT function
Hunger, sleep, arousal, aggressive behaviour
Endorphins NT function
Act with the pain pathways and emotion centres of the brain
Excitatory NT’s cause**….
Depolarisation
Inhibitory NT’s cause**….
Hyperpolarisation