quick practise

what are the three types of nerve fibres

type a: large diamater, myelinated

• conduct 15-20 m/s

• motor neurons, skeletal muscle, or sensory neurons

type b: medium diameter; light myelination

• conduct 3-5 m/s

• autonomic system( like smooth and cariac muscle)]

type C: small diameter, no myelination

• conduct 2 m/s

• autonomic system (like digestive tract)

What are ways to get rid of neurotransmitters?

• diffusion along conc gradient

• enzyme degeneration: example acetylcholinesterase breaks down acetylcholine and it gets recycled in presynaptic membrane back to acetylcholine

• reuptake by neurons or glial cells

—> norepinephrine gets reuptaken

—> prozac: used to treat depression by inhibiting reuptake of serotonin

spatial summation

several different axons come to the neuron cell body and release neurotransmitter. these neurotransmitters may cause ESPS or IPSP, so graded potential is the overall change when you add those

temporal summation

occurs when 2 or more axons signals are received at a neuron within a short time, causing the effects of the neurotransmitters to accumulate and potentially trigger an action potential.