FOUNDATIONS: STRUCTURE OF NERVOUS SYSTEM Flashcards
What is a subdural hematoma?
A collection of blood in between the dura and arachnoid mater from ruptured blood vessels passing through the dura. This can compress parts of CNS and is treated by drilling a hole in skull to drain blood
Where are motor neuron cell bodies located?
Ventral root horn
Where are sensory root cell bodies located?
In the dorsal root ganglion
What does the diencephalon contain?
The thalamus, hypothalamus, pituitary gland and pineal gland
What is the cerebral cortex and what are its functions?
The outermost sheet of neural tissue (functions in sensory perception, motor control, cognition)
What is the basal ganglia?
4 internal nuclei that form feedback circuits with the cerebral cortex- critical in motor control, behaviour switching, learning, reward
What is the limbic system and what structures does it contain?
Collection of nuclei grouped for their location rather than a function (limbus means border).
- Contains hippocampus (memory), amygdala (emotional valence and importance of stimuli-reward/fear)
Is there a space between the dura and arachnoid mater OR between the arachnoid mater and pia mater?
Arachnoid and pia mater!! This is the sub arachnoid space and contains CSF.
What is abundant in pia mater?
BLOOD VESSELS
What do the ventricles do?
Carry metabolic waste from brain back to bloodstream
How many ventricles are there in the brain and what are the names of them?
There are 4 ventricles; 2 lateral ventricles, a third ventricle and a fourth ventricle (base of brain)
What is the function of the blood-brain barrier?
Restricting entry of macro molecules into the brain (shields brain from abnormal variations in ionic composition and potentially toxic molecules (drugs, ingested poisons)
What does is the blood brain barrier a result of?
Tight junctions between endothelial cells and capillaries
Which types of neurons regulate blood flow?
Astrocytes
Which structures separate blood flow between the body and brain?
Blood brain barrier and circle of willus
What is the function of the circle of willus?
Maintains blood flow (also with blood flow maintenance regulating pressure, concentration (CO2 O2) and pH)
What does the anterior cerebral artery supply?
The forebrain–> medial portions of the frontal lobes and superior medial parietal lobe
What does the middle cerebral artery supply?
Lateral cortex, anterior temporal lobes, insula.
What is an occlusion in neuroscience?
A blockage of a blood vessel
What is aphasia?
The inability to comprehend or speak language
What is segregation?
Spatial separation
What are clusters of brain regions known as?
Modules
What is functional integration?
Modules may be spatially separated, but they are functionally integrated
What does the cell-attached method of intracellular recording do?
- micropipette tip sealed onto the membrane
- Record single channels under patch of membrane without disrupting cytoplasm
What does the inside out and outside out method of intracellular recordings involve?
- Allows the study of single channels in isolated portions of the membrane
- Studies how changes on intracellular or extracellular surface of membrane alter ion channel function
(sucks a portion of membrane up -cleaves it from membrane)
What does the whole cell method of intracellular recordings work?
Records currents from multiple channels at once - Micropipette and cytoplasm are continuous
(sucks up either ends of membrane)
Which of the following processes dictate the amount of neurotransmitter released from a nerve ending on a short-term, MINUTE TO MINUTE, basis?
- Vescicle recycling in the nerve ending (recylcing may or may not involve fusion with the endosome)
- Calcium availability
- Neurotransmitter synthesis
Which processes are good on the LONG TERM basis in neurons?
Axoplasmic transport and vesicle synthesis in the cell soma
What is the major motor protein in RETROGRADE transport?
Dynein (slower transport)
If you are bitten by a dog with rabies, what happens?
The rabies virus travels retrogradedly back along the motor neurons–>spinal cord–> brain and then kills neurons- also affects other neurons because they are all interconnected
What does the axon terminal contain?
- Internal vesicles containing neurotransmitter
- protein dense
- ## lots of mitochondria
What does the axon terminal NOT contain?
- NO MICROTUBULES
What are neurites?
- Extensions from the cell body
dendrites and axons
Do microtubules and microfilaments change shape in dendrites and axons?
Their length is relatively stable however in mature neurons microtubules and microfilaments are dynamic so you can retract old ones and extend new ones (axons/dendrites)
What are mircotubules?
Longditudinally down neurites (axons and dendrites)
- Mediate intracellular transport
What do MAPs (microtubule-associated proteins) do?
Regulate microtubules assembly and function
- Help implicated in ALzhimers disease (tau acculmulates and could make microtubules tangle)
What are neurofilaments?
Provide strucutral support
- Regulate diameter of axons
What are microfilaments composed of ?
Actin molecules
- Linked to microtubules and membrane
What does the fact that dendrites have ribosomes under spines suggest?
- Info received at the synapse can control protein synthesis
- Could be mechanism underlying memory
What constrains a neurons function?
Its dendritic arbour (tree)
What are golgi type one neurons?
(projection neurons) - have long axons that extend from one part of the brain to the other e.g. pyramidal cells
What are golgi type II neurons?
Neurons that have short axons that do not extend beyond vicinity of the cell body (local circuit neurons)
