Name:
. Date:
.
How Neurons Communicate:
Exploring the different types of cell signaling in the Central Nervous System
Objectives:
• Identify the parts of the neuron and describe their function(s) in cell signaling
 Neurons conduct impulses by propagating axon potentials
• Understand various types of synaptic transmission
• Design and build a model to explain how several different types of cell signaling occur
in the central nervous system
Previous Knowledge Needed:
 Cells communicate with one another through chemical and/or mechanical signaling
 The process by which signals are received, processed and responded to, is called the
signal transduction pathway
 The nervous system controls communication between different parts of the body and
the body’s interactions with the environment
Introduction:
Neurons communicate with each other at synapses, the space between one neurons’
end and another neurons’ start. Synaptic transmission is the process by which a presynaptic (before the synapse) neuron communicates a chemical signal to a post-synaptic
(after the synapse) neuron. Although information signals flow through neurons electrically,
neuron communicate these signals chemically. Chemical signals are sent in tiny packages
called neurotransmitter vesicles. When a presynaptic cell is electrically activated by an
axon potential, the neuron releases neurotransmitter into the synaptic cleft. These tiny
packets bind to the surface of the postsynaptic neuron to initiate the signal transduction
pathway.
There are many ways in which neurons can send and receive signals, however. We
will explore, construct and present the following ways neuron communication can occur:
chemical signaling, electrical signaling, mechanical signaling, gaseous signaling, immune
cell signaling and hormone signaling.
Procedure:
Each group will be assigned a type of cell signaling, and will be responsible for
creating a poster describing: the process, the molecules involved and the outcomes of such
communication. You may use your textbooks to gather information and details about the
neuronal communication you are assigned. Each group will have 5 minutes present their
posters to the entire class. The class will be responsible for completing the activity
worksheet sections pertaining to each type of communication.
Materials:
Poster board, one per group
Markers
Tape
Glue sticks
Cut-out molecules involved in neuron communication
Biology books
Questions:
1. If neurons communicate chemically, what is the name of the area between neurons
where chemical signals can be released?
2. Name the three process of the “signal transduction pathway”.
a.
b.
c.
3. Give a short description of each type of cell signaling presented:
a. Chemical signaling
b. Electrical signaling
c. Mechanical signaling
d. Immune cell signaling
e. Hormone signaling
f. Gaseous signaling
4. True or False: hormone signaling causes activation of gene transcription.
5. Mechanical signaling can occur between cells by flow of ions and molecules through
what kind of cell membrane proteins:
a. Membrane receptors
b. Nuclear receptors
c. Gap junctions
d. Axon channels
6. Fill in the blank: Electric signals travels down a neurons’
by a process
called “saltatory conduction”. This conduction occurs by the synchronous opening
and closing of
channels that push along the current caused by ion flow.
Post-Lab Discussion
You should now have a better understanding of the many ways neurons
communicate in the brain to govern body functions. Though they can be very different,
each type is essentially similar in that important signals are sent and received through
electrical, chemical or mechanical ways, and that the receipt of these signals causes
changes in the receiving neuron to activate a response.
All types of cell signaling covered in this activity occur in healthy states. But what
happens when the brain is not healthy? Can you think of situations where the brain might
not be healthy? Discuss this with your neighbor. Write down your ideas here.
How might cell signaling be affected in conditions when the brain is not healthy?
We’ll discuss this as a class.