Molecular Biology of the Cell Chapter 014 Test Quiz Bank With Verified Questions & Answers 2023/2024
Lecture 13: Signal Transduction and G
... [Show More] 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 [Show Less]