Neuron Definition: a nerve cell; the basic building block of the nervous system.
Parts of the Neuron
1. Dendrite: the bushy, branching extension of neurons thatreceive messages and conduct impulses towards the cell body.
2. Cell Body: The cell’s life support center
3. Axon: the extension of a neuron, ending in branching terminal fibers, through whichmessages pass to other neurons or to muscles or glands.
2. Myelin Sheath
A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmissions speed of neuralimpulses as the impulse hops from one node to the next.
3. Functions of the Cell Body
Accepts incoming information from dendrites determines whether to pass on the information and contains thecell nucleus.
4. How neurons communicate. Action Potential.
Action Potential: a neuronal impulse; a brief electrical charge that travels down an axon. (The movements of positively charged ionsacross the membrane of a neuron).
Neurotransmitters are chemical messenger that cross the synaptic gaps between neurons. When released by the sending neuron, neurotransmitterstravel across the synapse and bind to receptors sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse. (Chemical released by axons, travel across synapsesand stimulate dendrites on other neurons).
“Morphine within” –natural, opiate like neurotransmitters linked to pain control and pleasure (Endorphins are neurotransmitters thatelevates mood and decreases pain).
An agonist molecule may be similar enough to neurotransmitter to mimic and increase its effect.
Antagonists block aneurotransmitter’s functioning. Inhibit the release of neurotransmitters.
9. Peripheral Nervous System
Peripheral Nervous System (PNS): the sensory and motor neurons that connect the central nervous system...