Lab1: Rat Brain Flashcards
Is the spinal cord located cordal or rostral to the brain?
Spinal cord is cordal to the brain.
A cross-section through the spinal cord is cut in which plane?
Coronal.
What is the approximate volume of the rat CNS?
3.5mL
State the 3 main differences of the rat brain compared to the human brain.
- Larger olfactory lobe relative to entire brain
- Smaller forebrain relative to whole brain
- Less folding
What is the largest crainial nerve visible on the rat?
Olfactory nerve.
Why is the olfactory nerve so large in the rat?
Connected to whiskers. Helps position the rat in space.
What is the 4th ventricle?
CSF-filled cavity from cerebral aqueduct to obex.
What info do each of the Ventral and Dorsal nerve roots carry?
Ventral = motor Dorsal = sensory
What is the thalamus’ function?
Relay system between brain and target organs.
What is the hypothalamus’ function?
Maintain homeostasis.
What is the function of the Periaqueductal grey region?
Process pain.
What is the functional role of the pons?
Contains many important nerves innervating head and face.
What is the corpus callosum?
Commisural fibres. Nerve tract connecting brain hemispheres.
What is the corona radiata?
Projection fibres (connects cortex with lower parts of brain).
What volume is the rat cerebellum, and so what proportion of the rat CNS does it comprise?
1mL. So ~33%.
Compare the density of neurons in the cerebellum compared to the rest of the brain.
Cerebellum is more densely packed with neurons.
What are the two functions of the flocculus?
- Input from inner ears to help with balance
2. Keeps eyes centrally positioned
Compare white and grey matter.
- Grey matter = cell bodies + dendrites for proccessing info
White matter = axons. Allows communication between grey matter and rest of body.
Compare the functional difference of the ventral horn and dorsal horn.
Ventral = carries motor info TO body parts Dorsal = carries sensory info FROM body parts
What is the difference between fasciculus cunneatus and fasciculus gracilus?
FC = sensory info from hands FG = sensory info from feet
How does proportion of white to grey matter vary between caudal and rostral regions of spinal cord?
More white matter from caudal to rostral (because receiving axons from more body parts as one moves up the body).
What is the function of Area Postrema?
Controls vomiting.
What is the function of the Vermis?
Controls body posture and locomotion.
