355 Exam April 10, 2024
Acetylcholine is degraded in the synaptic cleft by the enzyme:
Acetylcholinesterase
Acetylcholine is synthesized from:
Acetyl and choline
Acetylcholine receptors found in smooth muscles and the brain are:
Muscarinic and metabotropic
A characteristic feature of neuropeptides as neurotransmitters is:
They are synthesized at the ribosomes in the soma
A common feature of synaptic vesicles that distinguishes them from other vesicles in the neuron is:
The presence of specific proteins for neurotransmitter transport
Activation of GABA_B receptors leads to:
K+ efflux
Activation of metabotropic glutamate rececptors typically results in:
Activation of second messengers and diverse cellular responses.
Activation of metabotropic receptors generally results in:
Slower, longer-lasting responses
A distinguishing feature of synaptic vesicles that contain neuropeptides is:
They are made in the soma and transported down the axon
A drug that acts as a direct agonist for dopamine receptors would most likely:
Mimic the effects of dopamine and stimulate dopamine receptors
AMPA and Kainate receptors, types of glutamate receptors, generate excitatory postsynaptic potentials (EPSPs) through:
Na+ influx (because excitatory)
Amphetamines enhance neurotransmitter release primarily by:
Increasing the amount of NT released
A NT's action is terminated in the synaptic cleft by all of these mechanisms:
Reuptake into presynaptic neuron; enzymatic degradation; diffusion away from the synaptic cleft
Association cortex refers to areas that do what?
Integrate information from different sensory modalities
A very caudal coronal slice of the human brain is most likely to cut through which lobe?
Occipital lobe
Which lobe is rostral?
Frontal
Two types of receptors and what they mean:
1- Ionotropic: allows ions to cross
2- Metabotropic: use metabolic pathways
what makes the pore open?
transmitters binding to receptors
What channels do ionotropic receptors pass through?
Ligand-gated channel
Is Na excitatory or inhibitory?
Excitatory (recall depolarization)
Is Cl inhibitory or excitatory?
Inhibitory
What are metabotropic receptors linked to?
G-protein AKA glutamate
What kind of receptor is nicotinic?
Ionotropic (which means they pass through ligand-gated channels)
what kind of receptors are muscarinic ones?
Metabotropic (which means they are linked to G-protein; responses are slower)
What are the roles of D1 and D2?
Dopamine 1 activates adenylyl cyclase
Dopmine 2 inhibits adenylyl cyclase
is Dopamine ionotropic or metabotropic?
metabotropic
is GABA receptor ionotropic or metabotropic?
Both! two types of GABA
Discuss the effect of GABA (ionotropic) neurotransmitter on Cl-
GABA is an inhibitory NT. It allows for Cl- channel to which will ultimately help inhibitory drugs do their job.
Discuss effects of GABA (metabotropic) on K+
G-protein is activated which triggers K+ channels to open , then hyperpolarizatoin of cell (K+ leaves)
What determines the effect on the postsynaptic cell?
Receptor
What are some effects that NTs can have on receptors?
Excitatory and Inhibitory; fast and slow responses; changes in membrane potential
What do the wrinkles on the brain do?
Increase surface area
What is a visible difference between human brains and rat brains?
Rats don't have wrinkles
Rostral vs. Caudal meaning
Front vs. back
Ventral vs. Dorsal meaning
Front/bottom (stomach) vs. Back/above ("dos")
Term for side of body:
Lateral
Term for middle of body:
Medial
Describe what a coronal slice of the brain would look like.
Dviding front and back of brain
Describe what a horizontal slice of the brain would look like.
Dividing top from bottom
Describe what a sagittal slice of the brain would look like.
Dividing left hemisphere from right
Name the three major divisions of the brain.
Cerebrum, Cerebellum, Brain stem
Discuss how the brain is a growth of the spinal cord.
It's an enlargement of the front end of spinal into vesicles.
Describe the parts of the spinal cord
The spinal cord runs inside the vertebral column. Dorsal roots (top) and Ventral roots (bottom) allow for axons to enter the spinal cord. These roots form the spinal nerves. Ganglia contain cell bodies
The process in which reflexes arise:
Sensory info enters spinal cord (afferent)
Motor info exists spinal cord (efferent)
Are axons in white matter or grey matter?
White matter
What is the role of meninges?
Basically holding the brain together
Three types of mater in meninges:
Dura (tough), arachnoid (connective tissue), pia (carries small vessels). *empty arachnoid space: cerebrospinal fluid is present
Name the 5 ventricles in the brain
1- Lateral ventricle
2- Interventricular foramen
3- Third ventricle
4- Acqueduct of the midbrain
5- Fourth ventricle
What is produced in the ventricles?
Spinal fluid
Three steps to neural tube formation (during embryonic stage):
1. Groove in ectoderm
2. Neural folds and fuse
3. PNS develops from neural crest
Three vesicles formed in neural tube:
1- PROSENcephalon (forebrain)
2- MESENcephalon (midbrain)
3-RHOMBENcephalon (hindbrain)
Which two vesicles are part of the brain stem?
Prosencephalon and Mesencephalon
Where is the medulla oblongata located?
In the hindbrain and fourth ventricle
Where are the cerebellum and pons located?
Hindbrain
Where are the tectum and cerebral acqueduct located?
In the midbrain
What is the role of the cerebral acqueduct?
Passageway from third to fourth ventricle
Three components of the prosencephalon (forebrain):
- Telencephalic vesicles (hemispheres)
- Optic vesicles
- Diencephalon (thalamus and hypothalamus)
Describe how telencephalic vesicles become hemispheres.
They swell and grow posteriorally and laterally to cover the mindbrain and hindbrain. Cool!
In humans, which is the largest vesicle?
Forebrain
What are commisures?
fibers that are in the corpus callosum
Where do projection fibers travel?
From brain stem to forebrain
What is the thalamus for?
Sending sensory information (except olfaction) to the cerebral cortex
3 parts of the cortex in mammals:
Neocortex
Paleocortext
Archicortex