Molecular Biology of the Cell Chapter 014 Test Quiz Bank With
Verified Questions & Answers 2023/2024
Lecture 13: Signal Transduction and G Protein-Coupled Receptors correct answers
You need to be aware of 7 types of signaling at cell surface mechanisms
It is likely that you need to know the name the signal heading to the cell, the receptor it binds to and
what happens after. Some of these are large classes so there may be different effects
1. G protein-coupled receptors
2. Cytokine receptors
3. Receptor tyrosine kinases
4. TGFb receptors
Hedgehog receptors
5. Wnt receptors
6. Notch receptors correct answers
Although we have all these different kinds of cell receptor signaling pathways, they all operate under a
similar procedure: correct answers *Big picture for biomedical science = this is what happens when you
have an electrical signal being sent across a cell and it can not jump a chemical synapse so it must use a
singlaing molecule to cross the synapse*
1. Cell releases signal from vesicle
2. Vesicle fuses with cell membrane and releases signal
3. Signal binds to receptor
4. Signal transductions and second messengers
5. Impacts effector protein
6. Modification of gene expression
7. Signal leaves receptor and cascade stops
According to slide cell to cell communication from extracellular signaling involves six major steps:
(Why did he include a prior slide with 9+ steps?? who fukcing knows) correct answers 1. Synthesis of
signaling molecule by the signaling cell
2. Release of the signaling molecule by the signaling cell
3. Transport of signaling molecule to target cell
4. Detection of signal by specific receptor protein
5. A change in cellular metabolism, function, or development triggered by the receptor signal complex
6. Removal of signaling molecule which usually stops cellular response
It seems all are common sense but #5
We need signaling molecules to cross all different types of distances in the body. Define and explain:
1. Endocrine signaling
2. Paracrine signaling
3. Autocrine signaling
4. Signaling by plasma-membrane-attached proteins correct answers 1. Endocrine signaling
- Distance = far
- Hormone travel via blood
,- Allows one part of body to effect all of body (how epinephrine effects our whole body)
2. Paracrine signaling
- Distance = the cell beside it
3. Autocrine signaling
- Distance = none because it is signaling itself
4. Signaling by plasma-membrane-attached proteins
- Distance = short
- It is sending the signaling molecule through a protein to an adjacent cell (A protein bridge between to
cells)
How can you know where a hormone's receptor will be? correct answers You need to evaluate its water
affinity
Hydrophobic hormone = receptor in cytosol
Hydrophilic hormone = receptor on outer membrane surface
Since the membrane is hydrophobic, any hormone that is also hydrophobic will be able to cross through.
Think like to like
Although eh showed a slide of 6-7 types of receptors, it appears you just need to know four classes of
Cell Surface Receptors and what happens when a ligand binds to each
1. G coupled receptors
2. Ion-channel receptors
3. tyrosine kinase receptors
4. Receptors with intrinsic enzymatic activity correct answers 1. G coupled receptors - when a ligand
binds, the G protein activated and generates cAMP
2. Ion-channel receptors - when a ligand binds, the ion channel opens and ions flood through (action
potential dependent on these!)
3. tyrosine kinase receptors - when a ligand binds, idk what happens lmao
4. Receptors with intrinsic enzymatic activity - again idk whats happening here.
As mentioned in prior slides, hydrophilic hormones cannot come into the cell, so they must bind to G
coupled receptors and generate a second messenger to do their work.
What does hormone stimulation of G receptor activate?
What does this G coupled receptor activation synthesize in response?
What do cAMP and other similar second messengers activate?
What does cAMP specifically activate? correct answers What does hormone stimulation of G receptor
activate?
- adenylyl cyclase
, What does this G coupled receptor activation activate in response?
- Effector
What does effector do?
- Forms second messenger
What do and other similar second messengers activate?
- protein kinases
What does cAMP specifically activate?
- cAMP-dependent protein kinases (PKAs)
So know:
- hydrophilic hormone -> G coupled receptor -> Effector Adenylate Cyclase -> cAMP -> protein kinase A
correct answers
What are the four common intracellular second messengers activating?
1. cAMP
2. cGMP
3. DAG
4. IP3
Idk if im supposed to memorize the long ass name but i dont want to. Its on slide 482 though if i decide
to feel responsible correct answers 1. cAMP - this activates protein kinase A (PKA)
2. cGMP - this activates protein kinase G (PKG)
3. DAG - this activates protein kinase C (PKC)
4. IP3 - this opens Ca++ channels in the endoplasmic reticulum
Define signal transduction: correct answers An extracellular molecule binding and enacting a change
within the target cell
We have a few other conserved proteins involved in signal transduction: list the three correct answers 1.
GTPase switch proteins
2. Protein kinases
3. Adapter proteins - ligand binds and adapter recruits singlaing enzymes
Honestly just look at slide 483
Can you initiate the same kind of signaling pathway with a different receptor class? correct answers Yes,
especially if it is a common signaling pathway. This way we have multiple ways to get the same cellular
response
I think sometimes you can activate the G coupled receptor without the ligand even directly touching it:
correct answers 1. Ligand binds to the receptor of a cell that is coupled to a trimeric G protein
2. G protein is activated
3. Effector enzyme is activated (effector as in it actually does the work that affects the cell)
4. Effector enzyme makes the second messenger (often cAMP)
Verified Questions & Answers 2023/2024
Lecture 13: Signal Transduction and G Protein-Coupled Receptors correct answers
You need to be aware of 7 types of signaling at cell surface mechanisms
It is likely that you need to know the name the signal heading to the cell, the receptor it binds to and
what happens after. Some of these are large classes so there may be different effects
1. G protein-coupled receptors
2. Cytokine receptors
3. Receptor tyrosine kinases
4. TGFb receptors
Hedgehog receptors
5. Wnt receptors
6. Notch receptors correct answers
Although we have all these different kinds of cell receptor signaling pathways, they all operate under a
similar procedure: correct answers *Big picture for biomedical science = this is what happens when you
have an electrical signal being sent across a cell and it can not jump a chemical synapse so it must use a
singlaing molecule to cross the synapse*
1. Cell releases signal from vesicle
2. Vesicle fuses with cell membrane and releases signal
3. Signal binds to receptor
4. Signal transductions and second messengers
5. Impacts effector protein
6. Modification of gene expression
7. Signal leaves receptor and cascade stops
According to slide cell to cell communication from extracellular signaling involves six major steps:
(Why did he include a prior slide with 9+ steps?? who fukcing knows) correct answers 1. Synthesis of
signaling molecule by the signaling cell
2. Release of the signaling molecule by the signaling cell
3. Transport of signaling molecule to target cell
4. Detection of signal by specific receptor protein
5. A change in cellular metabolism, function, or development triggered by the receptor signal complex
6. Removal of signaling molecule which usually stops cellular response
It seems all are common sense but #5
We need signaling molecules to cross all different types of distances in the body. Define and explain:
1. Endocrine signaling
2. Paracrine signaling
3. Autocrine signaling
4. Signaling by plasma-membrane-attached proteins correct answers 1. Endocrine signaling
- Distance = far
- Hormone travel via blood
,- Allows one part of body to effect all of body (how epinephrine effects our whole body)
2. Paracrine signaling
- Distance = the cell beside it
3. Autocrine signaling
- Distance = none because it is signaling itself
4. Signaling by plasma-membrane-attached proteins
- Distance = short
- It is sending the signaling molecule through a protein to an adjacent cell (A protein bridge between to
cells)
How can you know where a hormone's receptor will be? correct answers You need to evaluate its water
affinity
Hydrophobic hormone = receptor in cytosol
Hydrophilic hormone = receptor on outer membrane surface
Since the membrane is hydrophobic, any hormone that is also hydrophobic will be able to cross through.
Think like to like
Although eh showed a slide of 6-7 types of receptors, it appears you just need to know four classes of
Cell Surface Receptors and what happens when a ligand binds to each
1. G coupled receptors
2. Ion-channel receptors
3. tyrosine kinase receptors
4. Receptors with intrinsic enzymatic activity correct answers 1. G coupled receptors - when a ligand
binds, the G protein activated and generates cAMP
2. Ion-channel receptors - when a ligand binds, the ion channel opens and ions flood through (action
potential dependent on these!)
3. tyrosine kinase receptors - when a ligand binds, idk what happens lmao
4. Receptors with intrinsic enzymatic activity - again idk whats happening here.
As mentioned in prior slides, hydrophilic hormones cannot come into the cell, so they must bind to G
coupled receptors and generate a second messenger to do their work.
What does hormone stimulation of G receptor activate?
What does this G coupled receptor activation synthesize in response?
What do cAMP and other similar second messengers activate?
What does cAMP specifically activate? correct answers What does hormone stimulation of G receptor
activate?
- adenylyl cyclase
, What does this G coupled receptor activation activate in response?
- Effector
What does effector do?
- Forms second messenger
What do and other similar second messengers activate?
- protein kinases
What does cAMP specifically activate?
- cAMP-dependent protein kinases (PKAs)
So know:
- hydrophilic hormone -> G coupled receptor -> Effector Adenylate Cyclase -> cAMP -> protein kinase A
correct answers
What are the four common intracellular second messengers activating?
1. cAMP
2. cGMP
3. DAG
4. IP3
Idk if im supposed to memorize the long ass name but i dont want to. Its on slide 482 though if i decide
to feel responsible correct answers 1. cAMP - this activates protein kinase A (PKA)
2. cGMP - this activates protein kinase G (PKG)
3. DAG - this activates protein kinase C (PKC)
4. IP3 - this opens Ca++ channels in the endoplasmic reticulum
Define signal transduction: correct answers An extracellular molecule binding and enacting a change
within the target cell
We have a few other conserved proteins involved in signal transduction: list the three correct answers 1.
GTPase switch proteins
2. Protein kinases
3. Adapter proteins - ligand binds and adapter recruits singlaing enzymes
Honestly just look at slide 483
Can you initiate the same kind of signaling pathway with a different receptor class? correct answers Yes,
especially if it is a common signaling pathway. This way we have multiple ways to get the same cellular
response
I think sometimes you can activate the G coupled receptor without the ligand even directly touching it:
correct answers 1. Ligand binds to the receptor of a cell that is coupled to a trimeric G protein
2. G protein is activated
3. Effector enzyme is activated (effector as in it actually does the work that affects the cell)
4. Effector enzyme makes the second messenger (often cAMP)
