Transcript Neurons
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:
– Neurons
which are the basic units of the nervous system.
Neurons
Receive, integrate, and transmit information
Operate through electrical impulses
Communicate with other neurons through
chemical signals
The Withdrawal Reflex
T
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 Neuron
Structure
Specific Parts: The Neuron
Function
1.
3.
2.
Neurons = 3 functions: Reception, Conduction, Transmission
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 touch
The 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.