Neuron Structure: 

The Neuron is a cell that is responsible for receiving and transmitting information inside of the nervous system.

The Cell Body is composed of 3 major parts that include the Cell body, Dendrites and Axon.

*Image above is from the textbook

The Cell body helps support the cell since it contains genetic information, and helps maintain the structure of the neuron and provides energy to help with the sequence of activities.

Axons are structures that carry impulses from the cell body to the axon terminal

Dendrites receive information from other neurons and bring it to the cell body

Other components of the Neuron include the Myelin Sheath, Schwann cell, Axon terminal, Synaptic knob, Nodes of Ravier and Nucleus.

Myelin Sheath covers the axon of some neurons and helps make neutral impulses work faster

Schwann cell helps protect the neuron by acting as an insulator and this helps prevent electrical impulses from passing through

Axon terminal forms connections with other cells

Synaptic knobs are connections that are formed between the dendrite and terminal of two different neurons

Nodes of Ravier speed up the rate of the signal connection

The Nucleus provides energy to the neuron, allowing it to perform its functions smoothly.

There are 3 types of Neuron Cells: Interneuron, Motor Neuron, and Sensory Neuron

The image above is called the Interneuron. 

The Interneuron is in charge of connecting the Sensory and Motor Neurons so they can exchange information and communicating with the Central Nervous System.

The image above is called the Motor Neuron. 

The Motor Neuron is in charge of relaying signals from the central nervous system to the rest of the body.

The image above is called the Sensory Neuron. 

The Sensory Neuron is in charge of transmitting signals from the outside of your body to the central nervous system.

Neuron Function: 

Action Potential moves along the Axon in multiple stages (Resting Potential, Depolarization, Repolarization and Resting State.

1. Resting Potential: Sodium and Potassium voltage gate channels are both closed. At this state the axon is polarized because the negative and positive ions are equally balanced.

2. Depolarization: The Sodium channels open due to a stimulus causing sodium to rush into the cell and the voltage to increase. Depolarization causes the ions on the axon membrane to be imbalanced. This causes pores on the membrane to also open up and along more charged ions in while the original section is pumping the sodium ions out of the body.

3. Repolarization: The Sodium ions increase until they reach a point of 40 mV when they close and then the potassium voltage channels open. The potassium rushes out of the cell, and it causes the voltage to rapidly decrease.

4. Resting state: Both Sodium and Potassium channels are closed. Sodium potassium exchange pumps moves Sodium out of the cell and Potassium into the cell. This brings them back to normal polarity and resting potential

Synapse Structure:

Down below is an image of Synapse with it’s labelled parts.

Synapse Function: 

The Synapse allows a neuron to pass an electrical signal onto another neuron and this is very important for transferring impulses from one end to another.

This process begins when the nerve impulse reaches the terminal button and it starts releasing Neurotransmitters into the Synapse.  The Neurotransmitters moves into the Synapse and fits into receptors on the dendrites that are located on the opposite side (fits like a lock and key) When the neurotransmitters attach to receptors on the neuron side of the Synapse they produce an excitatory or inhibitory effect. If the neuron side takes in more than one neurotransmitter, it is influenced by the excitatory and inhibitory effect. If the excitatory effects outnumber the inhibitory effects, then it will begin transferring information into the next neuron. In order for the next potential stimulation to occur, neurotransmitters that are not accepted by the receptor sites must be removed from the Synapse. Enzymes will break down the neurotransmitters, which will then be reabsorbed by the terminal buttons and this process will be able to start again.