Week Six:neuronmusclar Junction

Front 1

step one

Back 1

a nerve impulse reaches the end of the motor neuron

Front 2

step two

Back 2

calcium channels into the axon bulb open, allowing calcium ions to diffuse into the bulb

Front 3

step three

Back 3

the calcium ions cause vesicles of acetylcholine to move to the membrane of the bulb, where they open dumping acetylocholine into the synaptic cleft

Front 4

step four

Back 4

acetylcholine spreads throughout the synaptic cleft by diffusion. (Some will reach the receptors on the motor end plate and will bind)

Front 5

step five

Back 5

if enough acetylocholine binds to the receptors, the muscle cells will contract

Front 6

what the muscle cells contract what is this called?

Back 6

the point where contraction occurs is the threshold of the muscle cell

Front 7

how does stimualtion end? first thing?

Back 7

acetylcholine is released from the receptors

Front 8

second thing for stimulation to end?

Back 8

some of the acetylcholine will be destroyed by enezymes in the cleft

Front 9

third thing for stimulation to end?

Back 9

acetylcholine is pumped back into the bulb, where it is available to be used again

Front 10

what is inside a vesicle?

Back 10

a neurotransmitter called ACETYLCHOLINE