GMS 6504 UPDATED 2026 EXAM SCRIPT QUESTIONS AND
ANSWERS SCORED A+
✔✔What are the two types of binding that happen in binding experiments? - ✔✔Specific
binding - Drug bound to target site
Nonspecific binding - Bound anywhere else; Requires competitive inhibitor to determine
✔✔What is the formula for specific binding? - ✔✔[A]/[A] + Kd
✔✔What is the formula for nonspecific binding? - ✔✔nsb = k*[A]
✔✔What is the formula for total binding? - ✔✔([A]*Bmax /[A] + Kd ) + k * [A]
✔✔What is a Scatchard Plot? - ✔✔plots the total amount of bound ligand divided by its
free concentration (B/[L]) against the total bound ligand, B.
✔✔What are the three types of displacement binding? (3) What is there impact on
IC50? - ✔✔Competitive - As the concentration of radioligand goes up, IC50 goes up.
Noncompetitive - IC50 does not change with increasing radioligand
Allosteric - IC50 goes up with increasing radioligand Complete inhibition is not possible
at high concentrations of radioligand (saturable)
✔✔What are the first 4 criteria for Binding Experiments? - ✔✔1. The binding is saturable
2. The binding is reversible and able to be displaced by other ligands
3. There is a ligand available to determine non-specific binding.
4. There is sufficient biological binding material to yield a good signal-to-noise ratio but
no too much so as to cause depletion of the tracer ligand.
✔✔What are the second 4 criteria for Binding Experiments? - ✔✔5. For optimum
binding experiments, the following conditions should be met: There is a high degree of
specific binding and a concomitantly low degree of non-specific binding
6. Agonist and antagonist tracer ligands are available
7. The kinetics of binding are rapid
8. The ligand used for determination of non-specific binding has a different molecular
structure from the tracer ligand.
✔✔What are the assay groups? - ✔✔1, 2, 3
✔✔What is Assay group 1?
What is an example pf how it is tested? - ✔✔- Measure cell/tissue function
- Highly amplified
, ---Most sensitive
---Partial agonists appear as full agonists
-----Can't compare agonists
Microphysiometry - in vitro measurement of the functions and activities of life or of living
matter and of the physical and chemical phenomena involved on a very small scale.
✔✔What is Assay group 2? - ✔✔- Measure second messengers
- G proteins activate adenylate cyclase
---Measure cAMP
- Calcium flux influences many cellular processes
---Measure calcium concentration
-----Transient
✔✔What is Assay group 3? - ✔✔Measure cell products
---cAMP activates many enzymes
---Transfect cAMP inducible luciferase
---Can allow to build overnight for easy detection
-----Drug may be toxic for long time points
✔✔How are GPCR Internalized? - ✔✔β-arrestin internalizes activated GPCRs (GDP
exchanged for GTP)
✔✔What are the minimal criteria for experiments utilizing cellular function? (2) - ✔✔1.
An agonist and antagonist to define the response of the target are available
2. The agonist is reversible (after washing with drug free medium)
✔✔What are the optimal criteria for experiments utilizing cellular function? (5) - ✔✔1 the
response should be sustained and not transient. No significant desensitization of the
response occurs within the time spent of the experiment
2 The response production should be rapid
3 The responses can be visualized in real time
4 There are independent methods to either modulate or potentiate functional responses
5 There is a capability to alter the receptor density (or cells available with a range of
receptor densities)
✔✔MOD 3 - ✔✔
✔✔Surmountable (unsaturable) antagonism is - ✔✔antagonism with no diminution of
maxima and not limiting antagonism. COMPETITIVE ANT
looks like that original graph but continuously shifted to the right
✔✔Surmountable antagonism - ✔✔dextral displacement to a limiting value produced by
an allosteric modulator. NONCOMPETITIVE ANTAG
ANSWERS SCORED A+
✔✔What are the two types of binding that happen in binding experiments? - ✔✔Specific
binding - Drug bound to target site
Nonspecific binding - Bound anywhere else; Requires competitive inhibitor to determine
✔✔What is the formula for specific binding? - ✔✔[A]/[A] + Kd
✔✔What is the formula for nonspecific binding? - ✔✔nsb = k*[A]
✔✔What is the formula for total binding? - ✔✔([A]*Bmax /[A] + Kd ) + k * [A]
✔✔What is a Scatchard Plot? - ✔✔plots the total amount of bound ligand divided by its
free concentration (B/[L]) against the total bound ligand, B.
✔✔What are the three types of displacement binding? (3) What is there impact on
IC50? - ✔✔Competitive - As the concentration of radioligand goes up, IC50 goes up.
Noncompetitive - IC50 does not change with increasing radioligand
Allosteric - IC50 goes up with increasing radioligand Complete inhibition is not possible
at high concentrations of radioligand (saturable)
✔✔What are the first 4 criteria for Binding Experiments? - ✔✔1. The binding is saturable
2. The binding is reversible and able to be displaced by other ligands
3. There is a ligand available to determine non-specific binding.
4. There is sufficient biological binding material to yield a good signal-to-noise ratio but
no too much so as to cause depletion of the tracer ligand.
✔✔What are the second 4 criteria for Binding Experiments? - ✔✔5. For optimum
binding experiments, the following conditions should be met: There is a high degree of
specific binding and a concomitantly low degree of non-specific binding
6. Agonist and antagonist tracer ligands are available
7. The kinetics of binding are rapid
8. The ligand used for determination of non-specific binding has a different molecular
structure from the tracer ligand.
✔✔What are the assay groups? - ✔✔1, 2, 3
✔✔What is Assay group 1?
What is an example pf how it is tested? - ✔✔- Measure cell/tissue function
- Highly amplified
, ---Most sensitive
---Partial agonists appear as full agonists
-----Can't compare agonists
Microphysiometry - in vitro measurement of the functions and activities of life or of living
matter and of the physical and chemical phenomena involved on a very small scale.
✔✔What is Assay group 2? - ✔✔- Measure second messengers
- G proteins activate adenylate cyclase
---Measure cAMP
- Calcium flux influences many cellular processes
---Measure calcium concentration
-----Transient
✔✔What is Assay group 3? - ✔✔Measure cell products
---cAMP activates many enzymes
---Transfect cAMP inducible luciferase
---Can allow to build overnight for easy detection
-----Drug may be toxic for long time points
✔✔How are GPCR Internalized? - ✔✔β-arrestin internalizes activated GPCRs (GDP
exchanged for GTP)
✔✔What are the minimal criteria for experiments utilizing cellular function? (2) - ✔✔1.
An agonist and antagonist to define the response of the target are available
2. The agonist is reversible (after washing with drug free medium)
✔✔What are the optimal criteria for experiments utilizing cellular function? (5) - ✔✔1 the
response should be sustained and not transient. No significant desensitization of the
response occurs within the time spent of the experiment
2 The response production should be rapid
3 The responses can be visualized in real time
4 There are independent methods to either modulate or potentiate functional responses
5 There is a capability to alter the receptor density (or cells available with a range of
receptor densities)
✔✔MOD 3 - ✔✔
✔✔Surmountable (unsaturable) antagonism is - ✔✔antagonism with no diminution of
maxima and not limiting antagonism. COMPETITIVE ANT
looks like that original graph but continuously shifted to the right
✔✔Surmountable antagonism - ✔✔dextral displacement to a limiting value produced by
an allosteric modulator. NONCOMPETITIVE ANTAG
