Lab 8 The Nervous System BIO201L
Student Name:
Access Code (located on the lid of your lab kit):
Pre-Lab Questions:
”1. What is the primary function of the nervous system?”
The primary function of the nervous system is to gather and process sensory signals
from external environments and internal input from our body.
”2. Why does the cerebral cortex contain so many folds? ”
It helps increase the surface area.
”3. What is a nerve impulse? ”
A nerve impulse is a signal sent from the axon terminal down nerve fibers. It consists of
a wave of electrical depolarization that reverses potential difference across nerve cell
membranes.
”4. What are Schwann cells and what do they form? ”
Schwann cells are glial cells that keep peripheral nerve fibers alive. Glial cells are cells
that support neurons by surrounding them and keeping them insulated. These cells form
the myelin sheath.
”5. What is an all-or-none response? ”
The all-or-nothing response defines as the response strength to a nerve cell or fiber has
no correlation to the strength of the stimulus. In order for a nerve cell or muscle fiber to
respond it has to be above a certain threshold.
”6. What two effects might neurotransmitters have? ”
They can excite or inhibit nerve cells. Examples of these neurotransmitters are
acetylcholine and norepinephrine.
Experiment 1: Microscopic Anatomy of the Nervous System
Post-Lab Questions
”1. Label the arrows in the slide images below based on your observations from the
experiment. ”
A- Axon
B- Cell bodies
C- Myelinated axons
D- Myelin sheaths
,Lab 8 The Nervous System BIO201L
”2. What is the major function of the neuron? ”
They process and transmit information all over the body.
”3. Are the nodes of Ranvier spaced equally along the axon? Why is this significant? ”
Yes, this is significant because the distance in between signals affects the action
potential generated in response.
”4. Define depolarization. ”
, Lab 8 The Nervous System BIO201L
The difference in charge between the inside and outside of the plasma membrane
(nerve or muscle cell) due to a change in permeability and migration of sodium ions to
the interior
”5. Describe how Schwann cells form the myelin sheath and the neurilemma. ”
Schwann cells are individualized as single myelin sheath to form the axon. The sheath it
packed tightly in spiral casings around the axon. Schwann cells are another name for
neurilemma cells. These are both what are packed around the axon to form the myelin
sheath from the cell membrane.
”6. What determines whether a neuron is unipolar, bipolar, or multipolar? ”
The amount of signals being processed from the cell body is what determines if a
neuron is unipolar, bipolar, or multipolar.
Experiment 2: Virtual Model – The Nervous System
Post-Lab Questions
”1. Which feature is more superior, the sciatic nerve or the tibial nerve? ”
Sciatic nerve is more superior.
”2. What appendages is the radial nerve located in? ”
Posterior portion of the upper limb
”3. Where is the subcostal nerve located? ”
It is located along the lower portion of the T12.
”4. Is the brachial plexus anterior or superior to the lumbar plexus? ”
The brachial plexus is superior to the lumbar plexus.
Experiment 3: Virtual Model – The Nervous System Coloring Activity
”Upload image for each activity below: ”
”
Brain (Side View): ”
Student Name:
Access Code (located on the lid of your lab kit):
Pre-Lab Questions:
”1. What is the primary function of the nervous system?”
The primary function of the nervous system is to gather and process sensory signals
from external environments and internal input from our body.
”2. Why does the cerebral cortex contain so many folds? ”
It helps increase the surface area.
”3. What is a nerve impulse? ”
A nerve impulse is a signal sent from the axon terminal down nerve fibers. It consists of
a wave of electrical depolarization that reverses potential difference across nerve cell
membranes.
”4. What are Schwann cells and what do they form? ”
Schwann cells are glial cells that keep peripheral nerve fibers alive. Glial cells are cells
that support neurons by surrounding them and keeping them insulated. These cells form
the myelin sheath.
”5. What is an all-or-none response? ”
The all-or-nothing response defines as the response strength to a nerve cell or fiber has
no correlation to the strength of the stimulus. In order for a nerve cell or muscle fiber to
respond it has to be above a certain threshold.
”6. What two effects might neurotransmitters have? ”
They can excite or inhibit nerve cells. Examples of these neurotransmitters are
acetylcholine and norepinephrine.
Experiment 1: Microscopic Anatomy of the Nervous System
Post-Lab Questions
”1. Label the arrows in the slide images below based on your observations from the
experiment. ”
A- Axon
B- Cell bodies
C- Myelinated axons
D- Myelin sheaths
,Lab 8 The Nervous System BIO201L
”2. What is the major function of the neuron? ”
They process and transmit information all over the body.
”3. Are the nodes of Ranvier spaced equally along the axon? Why is this significant? ”
Yes, this is significant because the distance in between signals affects the action
potential generated in response.
”4. Define depolarization. ”
, Lab 8 The Nervous System BIO201L
The difference in charge between the inside and outside of the plasma membrane
(nerve or muscle cell) due to a change in permeability and migration of sodium ions to
the interior
”5. Describe how Schwann cells form the myelin sheath and the neurilemma. ”
Schwann cells are individualized as single myelin sheath to form the axon. The sheath it
packed tightly in spiral casings around the axon. Schwann cells are another name for
neurilemma cells. These are both what are packed around the axon to form the myelin
sheath from the cell membrane.
”6. What determines whether a neuron is unipolar, bipolar, or multipolar? ”
The amount of signals being processed from the cell body is what determines if a
neuron is unipolar, bipolar, or multipolar.
Experiment 2: Virtual Model – The Nervous System
Post-Lab Questions
”1. Which feature is more superior, the sciatic nerve or the tibial nerve? ”
Sciatic nerve is more superior.
”2. What appendages is the radial nerve located in? ”
Posterior portion of the upper limb
”3. Where is the subcostal nerve located? ”
It is located along the lower portion of the T12.
”4. Is the brachial plexus anterior or superior to the lumbar plexus? ”
The brachial plexus is superior to the lumbar plexus.
Experiment 3: Virtual Model – The Nervous System Coloring Activity
”Upload image for each activity below: ”
”
Brain (Side View): ”
