Nervous System
by Liam Gamble, Elizabeth Serunjogi,
Chloe Kolbet.
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Neurotransmitter and Chemical
Synapse
Chemical Synapse: the gap between the
output zone of a neuron (at the axon ending)
and the input zone of the adjacent cell or
neuron
Neurotransmitter: a signalling molecule
stored in the neuron's cytoplasm that when
released bridges gap and carries the
neuron's message to the adjacent cell or
neuron
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excitatory effect: drives cell to neuron
Visual
2 Examples of Neurotransmitters
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acetylcholine (ACh)
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location: muscle
at synapses between motor neuron and muscle cell
released from muscle cell, diffuses across gap, and
binds to receptors on muscle cells
excitatory effects: triggers action potential and
muscle contraction
Dopamine
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location: brain
carries emotional and pleasure messages
excitatory effects (higher focus) and inhibitory effects
(lower focus)
Electric to Chemical
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When an action potential reaches a nerve
terminal, it opens voltage-gated Ca2+
channels and allows Ca2+ to flow into the
terminal
The increased Ca2+ in the nerve terminal
stimulates the synaptic vesicles
to release their neurotransmitters
into the synaptic cleft
Stimulates Exocytosis
Receiving the Signal
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Neurotransmitters cross the neural
membrane through exocytosis
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Neurotransmitters bind to the postsynaptic
cell or neuron's membrane's receptors to
carry the signal
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Neuron recycles neurotransmitters using
reuptake protein pumps to retrieve
Summary video.
<http://tinyurl.com/2uaesl>
References
Neurogistics. The Brain Wellness Program, n.d. Web. 8
Nov. 2012. <http://tinyurl.com/c9cymba>.
Starr, Cecie, and Ralph Taggart. Biology: The Unity and
Diversity of Life. Pacific Grove, CA: Brooks/Cole, 2001.
Print. Cole Biology Series.
The Chemical Synapse. Youtube. StudentHelp4AP, 20 Jan.
2012. Web. 8 Nov. 2012. <http://tinyurl.com/d3kf8ku>.
McKinley, Michael, and Valerie O'Loughlin. Animation:
Chemical Synapse. Human Anatomy. Online
Learning Center, 2006. Web. 8 Nov. 2012.