(3 points) The major ATP-powered pump responsible for maintaining ion gradients across the plasma membrane of mammalian cells is:

(3 points) Which of the following conditions results in the fastest FRAP?

(3 points) Which of the following statements about a plot of V0 vs. for transport that follows Michaelis-Menten kinetics is false?   

(3 points) Sphingolipids (such as Sphingomyelin) differ from glycerolipids (such as phophatidylserine)

(3 bonus points) Briefly describe one finding noted in the article titled “How the coronavirus infects our cells”    

(3 points) Which of the following is the correct order of events for the regulation of cholesterol synthesis (1)        N-SREBP acts as a transcription factor controlling the expression of rate limiting enzymes in the cholesterol synthesis pathway (2)        at low cholesterol levels SREBP-SCAP traffics from the ER to the Golgi (3)        Golgi proteolytic enzymes cleave SREBP into N-SREBP (4)        Insig and SCAP–SREBP form the cholesterol sensor that is trapped in the ER at high cholesterol levels.

(3 points) Why do cells not have membrane transport proteins for O2?  

(3 points) In which of the following cases is energy NOT needed for transmembrane transport?

(3 points) The major ATP-powered pump responsible for maintaining ion gradients across the plasma membrane of mammalian cells is:

(3 points) The lateral diffusion of a plasma membrane protein has been studied using the fluorescence recovery after photobleaching (FRAP) technique in a cell under normal conditions, and the following plot has been obtained. Under a different condition, membrane protein complexes disassemble freeing partially-immobilized protein components. As a result, its lateral diffusion coefficient is increased. How would you expect the FRAP curve to change under these new conditions? The dotted line in each graph is the original curve shown for comparison.