Midterm 3 Flashcards
Where in the cell does Ca2+-ATPase mostly exist?
On the SR membrane
Where in the cell is ATPase catalytic domain of Ca2+-ATPase exposed?
Cytosol
Na+/K+-ATPase mainly exists on the ____ membrane, and the ATPase catalytic domain is exposed to the ____
Plasma
Cytosol
When the protein is free from any ion, phosphate, or ATP, its non-binding site is open to _____
Nucleus
Binding of ____ to the protein activates the ATPase
Na+
The ATP hydrolysis results in the covalent binding of the protein to _____
Phosphate
Covalent binding induces a conformational change of the protein. After this change, Na+ is released to _____
Extracellular space
Another ion, ____, binds to the protein. This indices the release of _____ so that the structure of the protein is back to original conformation
K+
Phosphate
Na+/K+-ATPase is a member of _____-type active transporters. This group of transporters includes _____
P
Ca2+-ATPase
What is most appropriate explanation of normal function of the Na+-Glucose symporter?
It transports Na+ only along the electrochemical gradient, but it transports glucose against (uphill) the gradient
Calculate membrane potential
V=62*log(Co/Ci)
K+ concentration inside = 198mM
K+ concentration outside = 15mM
-69.5mV
Which direction does K+ move through the channel?
K+ moves out of the cell
To reduce blood pressure, acetylcholine secreted from ____ stimulates _____ to produce nitric oxide NO
Parasympathetic neuron
Endothelial cell
NO enters the target cell _____ by _____
Smooth muscle
Simple diffusion
In the target cell, NO binds and activates the enzyme _____, which produces _____
Guanylyl cyclase
cGMP
