Parts of Neuron

Neuron

The basic, specialized cell in the nervous system that receives and sends messages within that system.

Dendrite

The branchlike structures of the neuron that receive messages from other cells and neurons.

Soma

Referred to as the "cell body". The part of the cell that contains the nucleus and keeps the entire cell alive and functioning (It is responsible for maintaining the life of the cell).
- integrates signals received from dendrites and passes them down the single nerve fiber the AXON.

Axon

Tubelike structure of neuron that carries the neural message from the cell body to the axon terminals, for communication with other cells.

Axon Terminals

Enlarged ends of axonal branches of the neuron, specialized in and responsible for communicating between cells.
-Where the neurotransmitters are released.

Glial Cells

Cells that provide support for the neurons to grow on and around, deliver nutrients to neurons, produce myelin to coat axons, clean up waste products and dead neurons, influence information processing, and, during prenatal development, influence the generation of new neurons.
- play role in learning, behavior, and neuroplasticity by affecting synaptic connectivity and facilitating communication between neurons in specific neural networks

Myelin

Layer of fatty substance created by special kinds of glial cells (Oligodendrocytes & Schwann cells).
-Wraps around shaft of axon, creating a protective, insulated layer and speeds up rate of transmission.

Where do Oligodendrocytes produce myelin ?

For the NEURONS in the BRAIN and SPINAL CORD
(Central Nervous System)

Where do Schwann cells produce myelin?

For the NEURONS of the BODY
(Peripheral Nerves)

Bundles of myelin-coated axons travel together as "________" in the CNS called ______________.

"Cables"

TRACTS

In the PERIPHERAL NERVOUS SYSTEM, bundles of axons are called ____________.

NERVES

Myelin from which glial cells, Oligodendrodytes or Schwann cells, HAS a unique feature that can serve as a tunnel through which damaged nerve fibers can reconnect and repair themselves?

SHWANN

Nerves

Bundled axons coated in myelin that travel through the body together and form neural "cables" connecting the central nervous system with muscles, glands, and sense organs.

Why does the message go down the coated axon much faster than it would an uncoated axon in the brain?

Because when the electrical impulse (the neural message) travels down an axon coated with myelin, the impulse is regenerated at each node and appears to "jump" or skip rapidly from node to node down the axon.

Diffusion

HIGH concentration to LOW concentration

Resting Potential

When the cell is resting (channels in the cell membrane are closed, sodium ions cannot enter).

Action Potential

When electrical potential is in action (when cells receives strong enough stimulation from other cells/dendrites activated, cell membranes open channels and sodium ions rush through)

Synaptic Vesicles

Little sac-like structures filled with chemicals suspended in fluid (found inside the synaptic knob), which are molecules of neurotransmitters.

Neurotransmitters

Substances that reside in the neuron and transmit messages.

Chemical messengers that are used to communicate with other neurons and other various types of cells.

Found in synaptic vesicles that, when released, has an effect on the next cell.

Synapse (Synaptic gap)

is a microscopic fluid filled space between the axon terminal of one cell (a neuron) and the dendrite or soma of the next cell (neuron).

Receptor Sites

3D Proteins on the surface of dendrites or certain cells of muscles and glands that allow only particular molecules (NEUROTRANSMITTERS) of a certain shape to fit into. (key-lock model)