INTRODUCTION TO NEUROSCIENCE Flashcards
Name the types of Neuron
Cerebellar Purkinjee cell
Cortical Pyramidal cell - cortex
Hippocampal granule cell - hippocampus
Retinal Bipolar cell - eye
What is resting potential of electrically charged neurons?
70 millivolts
What is the name for charged particles differently distributed on either side of the cell membrane?
Ions
What type of ions are there?
A anions restricted to the inside of the cell
Na+ Sodium ions mostly outside the neuron
K+ mostly inside the neuron
Cl- mostly outside the neuron
What characteristic can be used to describe the neuronal membrane?
Semi-permeable
What is the connection between the lipid bilayer and negative ions
it is impermeable
Channel allows the flow of —-
specific ion through the membrane
When there is different concentration =s of ions in and out of the cell, what two forces determine distribution of charged ions?
1) Diffusion - high concentration to low concentration - equal quantity
2) Electrostatic pressure - Likes repel and Opposites attract.
What effect does diffusion and electrostatic pressure have on ion distribution?
Sodium potassium pump keeps positive sodium out of active processes.
Active process Na+ ions out of neuron and K+ in.
Three Na+ for every two K+
Require energy provided by ATP.
What is resting potential when forces balance?
70mV
What happens when there is high concentration of Na+ outside the cell?
Both forces push in.
What does the membrane and pump do in response?
Resists Na+ inward movement
K+ and Cl- can move backward and forward across the membrane until they reach …
steady state determined by opposing forces of diffusion and electrostatic pressure.
What happens to the sodium that leaks back in?
It is expelled by the pump. Information is then moved around the brain and body
Changing the membrane potential of postsynaptic potentials can induce
Excitatory postsynaptic potential
What is a EPSP
Depolarization occurs and response stimulatory
Depolarization might reach threshold producing an action potential and cell response.
What is an IPSP
Hyperpolarization and response inhibitory
Decrease action potentials by moving membrane potential farther from threshold.
What is spatial and temporal summation?
At any given moment, a neuron may receive postsynaptic potentials from thousands of other neurons. Whether threshold is reached, and an action potential generated, depends upon the spatial (i.e. from multiple neurons) and temporal (from a single neuron) summation of all inputs at that moment.
Describe the Action Potential
Threshold generate an action potential and axon requires a stimulus of a certain minimum strength
All or none each action potential has the same amplitude independently from the strength of the stimulus
Refractory period second action potential cannot occur during this period
Propagation of the action potential…
but depolarization is slow process sped up by myelin speeds up axonal conduction
What is saltatory conduction?
Information processing - synaptic transmission has five processes: 1 Manufacture 2 Storage 3 Release 4 Receptor Activation 5 Inactivation and reuptake
Common neurotransmitters are…
Fast neurotransmitters - short lasting effects - Acetylcholine (ACh) - Glutamate (GLu) - Gamma aminobutyric acid (GABA) Neuromodulators - - Dopamine (DA) - Noradrenalin (NA) - Serotonin (5HT)
