Term
| How does concentration of a ligand affect its probability of binding to a receptor? |
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Definition
| the higher the concentration of ligand molecules, the higher the probability one will find a receptor & bind to it |
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Term
| How does ligand-receptor affinity affect probability of their binding? |
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Definition
| the higher the affinity (attraction) of a ligand for a receptor, the higher the probability the ligand will bind to it |
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Term
| dissociation constant (KD) |
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Definition
| the concentration of a ligand at which 50% of the receptors are occupied |
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Term
| Why do some alpha-GTPs get mopped up by RGS? |
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Definition
| there are so many of them that they don't all go to effector proteins |
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Term
| Can an effector protein interact with more than one alpha-GTP in a given metabotropic response? |
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Definition
| yes! (after an alpha-GTP degrades after interacting with an effector protein, another alpha-GTP can interact with the same protein) |
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Term
| In the discovery of secondary messengers experiments, we were dealing with _____ liver |
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Definition
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Term
| discovery of secondary messengers, experiment 1: membrane, LP in a test tube + EPI --> ? |
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Definition
| membrane, phosphorylated LP in a test tube |
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Term
| discovery of secondary messengers, experiment 2: membrane, LP in a test tube --> centrifuged membrane, LP in a test tube --> LP (no membrane pellet!) in a test tube + EPI --> ? |
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Definition
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Term
| discovery of second messengers, experiment 3: membrane, LP in a test tube + EPI --> membrane, phosphorylated LP in a test tube --> centrifuged membrane, LP in a test tube --> leftover liquid (not membrane, LP pellet) in test tube + LP --> ? |
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Definition
| phosphorylated LP in a test tube |
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Term
| When looking at current traces, it is crucial to look at the ______ scale!! |
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Definition
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Term
| 2 phenomenon that still allow GABA "A" receptors to have an inhibitory influence, even when membrane potential = chloride equilibrium potential |
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Definition
1. blunting inhibition
2. shunting inhibition |
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Term
| When membrane potential = chloride equilibrium potential, do you get an IPSP? |
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Definition
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Term
| When membrane potential > chloride equilibrium potential, you get an ______ |
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Definition
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Term
| When membrane potential < chloride equilibrium potential, you get an ______ |
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Definition
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Term
| GABA "A" opens ______ channels |
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Definition
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Term
| weird spine ganglion experiment: stimulate once --> ? |
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Definition
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Term
| weird spine ganglion experiment: train of stimuli --> ? |
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Definition
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Term
| weird spine ganglion experiment: slow EPSP happens & you give a single stimulus during the slow EPSP --> ? |
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Definition
| normal EPSP "rides" on top...longer & higher than usual |
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Term
| What was the goal of the experiment involving a cell with mAChR & somatostatin receptor (metabotropic also) & calcium channels? |
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Definition
why do you get specificity?
*result: even if you do get the same result, the g-protein makeup on each metabotropic receptor is not exactly the same (why the oligos for one G-protein doesn't work for the other) |
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Term
| Are non-NMDA (AMPA, kainate) or NMDA receptors faster when it comes to response time? |
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Definition
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Term
| How is GTP/GDP used for metabotropic receptor activation? |
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Definition
| GTP is present in surplus & binds to the alpha subunit, activating the receptor |
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Term
| Is GDP ever in surplus to GTP or are they every in an equal amount? |
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Definition
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Term
| The specificity of a g-protein complex's activity within a neuronal cell is primarily dependent on ______ |
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Definition
| the activated primary effector protein |
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Term
| Does the neurotransmitter give specificity to the g-protein complex's activity in a cell? |
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Definition
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Term
| Does the g-protein GTPase mechanism itself give specificity to the g-protein complex's activity in a cell? |
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Definition
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Term
| Does the beta subunit give specificity to the g-protein complex's activity in a cell? |
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Definition
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Term
| What is the primary effector in the following pathway: histamine --> histamine receptor --> Go --> PLA2 --> arachidonic acid --> breakdowns of the acid |
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Definition
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Term
| What is the secondary messenger in the following pathway: histamine --> histamine receptor --> Go --> PLA2 --> arachidonic acid --> breakdowns of the acid |
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Definition
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Term
| What is the secondary effector in the following pathway: histamine --> histamine receptor --> Go --> PLA2 --> arachidonic acid --> breakdowns of the acid |
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Definition
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Term
| T/F: a neurotransmitter is excitatory or inhibitory unto itself |
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Definition
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Term
| T/F: a neurotransmitter's activity is dependent on the type of receptor it binds to |
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Definition
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Term
| T/F: a neurotransmitter can bind to various types of receptors |
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Definition
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Term
| T/F: a given neurotransmitter can have various indirect effects in a cell |
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Definition
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Term
| T/F: neurotransmitter release can be regulated by a feedback loop acting on the presynaptic cell |
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Definition
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Term
| T/F: inactivation happens when GTP gets cleaved down to GDP |
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Definition
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Term
| T/F: inactivation happens when the alpha, beta, & gamma subunits are bound with GDP |
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Definition
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Term
| T/F: when there is GDP bound, the alpha subunit loses its affinity for the beta-gamma dimer & the two dimers separate |
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Definition
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Term
| T/F: the overall alpha, beta, gamma, GDP cluster has a low affinity for the metabotropic receptor |
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Definition
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Term
| The study by Dr. Sutherland on effects of epinephrine on liver cells proved that ______ |
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Definition
| a soluble messenger transduces the signal between the membrane & the cytoplasmic enzyme |
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Term
| T/F: metabotropic receptors have a rapid termination of effects |
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Definition
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Term
| T/F: receptors are only located postsynaptically |
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Definition
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Term
| T/F: only neurotransmitter dictates the effect in the postsynaptic neuron |
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Definition
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Term
| T/F: GABA will always have an inhibitory postsynaptic effect |
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Definition
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Term
| T/F: ionotropic receptors are normally located near the site of neurotransmitter release |
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Definition
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Term
| 3 things that could impact the probability of ligand X binding to receptor Y |
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Definition
1. concentration of ligand X
2. affinity of ligand X for receptor Y
3. presence of antagonist Z |
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Term
| Why is a g-protein not always active if there is much more GTP than GDP in the cytosol? |
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Definition
| the alpha subunit has a much higher affinity for GDP than for GTP |
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Term
| definition of a secondary messenger |
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Definition
| what is created/acted on by the primary effector |
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Term
| T/F: a neurotransmitter can either bind to an ionotropic or a metabotropic receptor (but not both) |
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Definition
| false! (ex. ACh, glutamate, GABA) |
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Term
| Is GABA "B" an ionotropic receptor? |
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Definition
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Term
| Are NMDA receptors ionotropic receptors? |
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Definition
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Term
| Are GABA "A" receptors ionotropic receptors? |
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Definition
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Term
| Are nAChRs ionotropic receptors? |
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Definition
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Term
| Are ionotropic receptors ligand-gated? |
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Definition
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Term
| Are ionotropic receptor effects fast onset? |
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Definition
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Term
| Do ionotropic receptor effects have an early/fast termination? |
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Definition
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Term
| Do ionotropic receptors have a 1:1 action:response ratio? |
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Definition
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Term
| Are ionotropic receptor effects limited by neurotransmitter availability only? |
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Definition
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Term
| Are ionotropic receptors located near the site of neurotransmitter release? |
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Definition
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Term
| T/F: the binding of a ligand at a given concentration is probabilistic & is not guaranteed? |
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Definition
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Term
| T/F: metabotropic receptors are ligand-gated ion channels? |
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Definition
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Term
| T/F: competitive antagonists permanently interfere with ligand binding |
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Definition
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Term
| T/F: RGS accelerate alpha subunit GTPase activity & also help the alpha subunit initiate biochemical cascades |
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Definition
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Term
| T/F: only ionotropic receptor responses can cause ion channels to open |
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Definition
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Term
| Do non-NMDA or NMDA receptors open at a lower membrane potential? |
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Definition
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