Question:
A brain neuron is in synaptic relationship with 2 other neurons, one excitatory and one inhibitory.

A) Explain what is meant by this, including the following terms in your answer: axon terminal, cell body, dendrite, membrane, neurotransmitter, neurotransmitter receptor, synapse. Labeled diagram encouraged, but we also want your verbal explanation.

B) What happens to the first neuron when the excitatory neuron fires?

C) What happens to the first neuron when the inhibitory neuron fires?

Answer:
A) Typical nerbve cells are composed of dendrites (that receive signals from other nerve cells) that project from a central cell body (which contains the nucleus and other machinery necessary for the cell to survive) and a long axon, which carries signal and ends in an axon terminal. A neuron in a synaptic relationship means that it can communicate with other neurons through an axon terminal-dendrite connection. For the electrical signal to cross the neuronal membrane and the synapse, the space between the axon terminal and the dendrite, it must be turned into a chemical signal, carried by neurotransmitters. These neurotransmitters are hormones that are released from the axon terminal of a neuron upon firing and cross the syaptic space. Neurotransmitter receptors on the dendrites of the adjacent neuron pick up these signals and respond in a specific manner, depending on whether the signal is excitatory or inhibitory.

B) When the excitatory neuron fires, it releases neurotransmitters that encourage the firing of the synapsed neuron by making depolarization easier. These neurotransmitters can cause the neuron to fire longer or more frequently, resulting in a stronger signal to downstream neurons

C) When an inhibitory neuron fires, it releases neurotransmitters that lead to the hyperpolarization of the neuronal membrane, thus making it more difficult to fire, and decreasing signal strength or frequency.