Neurons and Neurotransmitters

by Diana Last modified by: Ashley Heather Brock last Modified by Angela Sagner

The Nervous System• A physical organ system like any other

• The main kind of cell we are studying today:– Neuronswhich are the basic units of the nervous system.

Receive, integrate, and transmit information

Operate through electrical impulses

Communicate with other neurons through chemical signals

Neurons

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The Withdrawal Reflex

Neuron Anatomy and Neural Communication

Neural Anatomy Dendrite

the bushy, branching extensions of a neuron that receive messages and conduct impulses toward the cell body

Axon the extension of a neuron, ending in

branching terminal fibers, through which messages are sent to other neurons or to muscles or glands

Neural Anatomy and communication

Synapse junction between the axon tip of the sending

neuron and the dendrite or cell body of the receiving neuron

Cell Body-main body connected to dentrites and axon

Specific Parts: The NeuronStructure

Specific Parts: The Neuron Function

Neurons = 3 functions: Reception, Conduction, Transmission

1.3.

2.

ACTION POTENTIAL VIDEO

Relay Race

Action Potential starts at the dendrite, travels through the cell body, down the Axon to the Axon Terminals.

• How does it get to the next cell’s dendrites?

Neurons don’t touchThe Synapse has a millionth inch gap.In the synapse there are vesicles w/

neurotransmitters that are chemical messengers that transmit info to the next dendrite.

How does it get to the next cell’s dendrites?

Neurotransmitters

chemical messengers that traverse the synaptic gaps between neurons

when released by the sending neuron, neurotransmitters travel across the

synapse and bind to receptor sites on the receiving neuron, thereby influencing whether it will generate a neural impulse

Myelin Sheath– Fatty material – Insulates the axon– Allows for rapid movement of

electrical impulses along the axon– The Nodes of Ranvier are gaps in the

myelin sheath where action potentials are transmitted.