Local Potentials

What is the resting membrane potential?

-70mV

What three things cause the inside of the cell to be negative relative to the outside?

1. sodium-potassium pump

2. leak channels

3. large anionic proteins

What travels down the axon of the presynaptic neuron?

action potential

The action potential that travels down the axon of the presynaptic neuron open ____ gates calcium channels in the axon terminal.

voltage

What enters the axon terminal and causes vesicles containing neurotransmitters to fuse with the cell membrane and release via exocytosis?

calcium

What diffuses across the synaptic cleft and bind to the ligand-gated channels?

neurotransmitters

When sodium is let into the post-synaptic neuron, the message causes the neuron to ____. 

depolarize

Depolarization is an _____ message because the post-synaptic neuron gets closer to threshold.

excitatory

What is threshold in mV?

-55 mV

If chlorine is let into the post-synaptic neuron, the message causes the neuron to ___.

hyperpolarize

Hyperpolarization is an ____ message because the post-synaptic neuron gets farther from threshold.

inhibitory

If potassium is let out of the post-synaptic neuron, the message causes the neuron to ___.

hyperpolarize

Name two ways local potentials differ from action potentials?

1. differ in strength (can be larger or smaller), whereas action potentials are all the same size

2. local potentials get weaker as they travel down the axon. action potentials do not