Brain Dissection
How to perform a successful
brain dissection
• Perform each step of the lab, referring to this
power point for guidance.
• Carefully study each structure and think about
what it does.
• Discuss the details of each structure with your
partner and develop cues that will help you
during the test.
• Label each structure on the brain diagrams.
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STEP 1
Use a scissors to cut away the covering around the brain
known as the dura mater.
Be careful on the anterior side of the brain. Nerves (white,
cord-like structures) should remain attached to the brain.
A skilled dissector can remove it in one piece.
Describe the dura mater. Be specific.
Use a forceps to gently pull on the surface of the brain. You
may be able to grab hold of the arachnoid mater.
STEP 2
• Find the cerebrum, cerebellum and brain
stem.
• What is the function of each structure?
• How can you remember each structure for the
test?
cerebrum
cerebellum
Brain stem
• Study the shape, size and texture of the total
structure.
• Compare the photos of a human brain to your sheep
brain.
STEP 3
• Notice the ridges and grooves in the cerebrum.
• What scientific names are given to these
structures?
• What is their purpose?
• Find the longitudinal fissure on the dorsal side
of the brain?
• What is a fissure?
STEP 4
• Observe the ventral side of the brain and begin at the anterior
end. You will see some of the major nerves associated with
your senses.
• Find the olfactory bulbs .
• Use your text to find out the sense associated with the
olfactory bulbs.
• What is a tract? (See page 232 in your text)
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Observe the optic nerves.
What sense are these nerves associated with?
The optic nerves cross as the optic chiasma.
Use the internet to find out the importance of
the crossing of optic fibers.
Optic nerve
Oculomotor nerve
• Observe some of the other anterior
structures. You will need to find the function
of the mammillary body on the internet.
-mammillary
body
-the pons
STEP 5
• Now make a midsagittal cut through the brain.
• Find and label the corpus callosum. What is
its function?
• Find the ventricles: This is a picture of the
lateral ventricle.
• What is the function of a ventricle?
• The 4th ventricle is connected to the 3rd
ventricle by the cerebral aqueduct.
• How do you think the cerebral aqueduct got
its name?
4th ventricle
Cerebral aqueduct
• Find the thalamus and label it on your
diagram.
• Describe its position in the brain.
• Find the structures of the brain stem: label
the medulla oblongata, pons and midbrain.
Spinal
cord
STEP 6
Make a coronal (frontal) section perpendicular
to the longitudinal fissure.
• Find the gray matter and white matter.
• The gray matter (also called the cortex) gets its
colors from what neuron structure?
• How does the white matter get its color?
Can you figure out the name of these openings?
STEP 7
Explore!!!!!
Myelinated axons
This brain was attached to the nasal bone. Note
how the nasal cavities fit over the olfactory
bulbs in real life.
Nasal cavities
Olfactory bulbs
STEP 8
• Throw the brain parts in the garbage.
• Wash and dry your dissection tray and tools.