Cell Signaling and Osmosis Practice Questions Flashcards
How are Simple Diffusion and Facilitated Diffusion related?
They depend on the concentration gradient
Which cellular process is coupled with hydrolysis of ATP?
Active Transport
When a plant cell is submerged in a very hypotonic solution, what is likely to occur?
The cells within the plant will grow large
From the perspective of the cell receiving the message, what are the three stages of cell signaling?
Signal Reception
Signal Transduction
Cellular Response
When does the process of transduction usually begin?
When the signal molecule changes the receptor protein in some way
Name 3 things that are true of ligand-gated ion channels?
They are important to the nervous system
They lead to changes in sodium and calcium concentrations
They open or close in response to a chemical signal
What would be true for the signaling system in an animal cell that lacks the ability to produce GTP?
It would not be able to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
Describe Cell Communication
In response to a signal, the cell may alter activities by changes in cytosol activity or in transcription of RNA
What does a receptor tyrosine kinases do?
Forms Dimmers
Adds Phosphate group
Activates relay proteins
Binding of a signal molecule to which type of receptor leads directly to a change in distribution of ions on opposite sides of the membrane?
Ligand-gated ion channel
The activation of receptor tyrosine kinase is characterized by what?
Dimerization and Phosphorylation
Epinephrine -> G protein- coupled receptor -> G protein -> Adenylyl cyclase -> cAMP
What is the secondary messenger?
cAMP
The amount and direction of movement of water in plants can always be predicted by measuring what?
Water Potential
An open beaker of pure water has a water potential of:
0.0 MPa
What does the equation iCRT
i: 1 or 2
C: Concentration
R: 0.0831
T: 273 + Temp.
