quiz #1- action potentials

roughly -70mV

• dendrites: receiving prongs
• axon: reduces from cell body to target cell
• Presynaptic terminal: fingerlike projections that are transmitting elements
• soma: where neurotransmitters are produced

in the cell

out of the cell

• high for potassium
• low for sodium

-120 mV

+35 mV

lose - charge

Try to get back to -70

increase - charge

-55 mV

• reestablish the concentration
• Na OUT of cell
• K IN cell

each synapse releases a set quantity of neurotransmitters

Presynaptic neuron releases a neurotransmitter into the synaptic cleft and the neurotransmitter diffuses from 1 side to another then binds to post synaptic neuron.

receptors for Ach blocked at neurotransmitter junction so the muscles don't contract

decreased serotonin produced in the brain

• neuromuscular junction
• basal ganglia
• parasympatheric post-ganglionic neurons

substantia nigra

• brain stem
• sympathetic post-ganglionic cells

brainstem

spinal cord- inhibitory

spinal cord- inhibitory

widespread- inhibitory

K+: causes hyperpolarization

Na+- causes depolarization

• combined effect of series of small potential changes causes depolarizations
• frequency of action potentials

• receptors or synaptic potentials in different regions added together to cause depolarization
• number of fibers processing action potentials

FALSE.

• axon diamter (more can get through at once)
• myelination (prevents leakage)

when an action potential proceedes down the myelinated axon jumping from node to node