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(A) Diagram the process of glucose transport from the lumen of the small intestine to the blood through an epithelial cell. (1 pt.) (B) Name the three transmembrane transporters involved, what they transport, and what energy sources they use.   Indicate where passive transport and primary and secondary active transport are involved and the relative (for example higher or lower) concentrations of Na+, K+, and glucose in the lumen, blood and cytoplasm and where uniport, antiport and symport are involved. (3 pts.) (C) Diagram and describe the mechanism of primary active transport by the Na+/K+ ATPase (Na+ pump). (5 pts.) (D) Oubain and digitoxin are drugs that inhibit the K+ dependent phosphatase activity of the Na+/K+ ATPase pump. How do these two drugs cause the heart muscle cells to contract more strongly in patients with heart disease?  (3 pts.) (E) Diagram or describe the mechanism of secondary active transport (symport) by Na+/glucose transporters using the electrochemical potential energy of a Na+ gradient to accomplish the active transport of glucose. How is the negative free energy change (-DG) of Na+ passage into the cell tied (physically) to transport of glucose against a concentration gradient? (3 pts.)

F-type ATPases in the apical domain of the plasma membrane.

mature through fusion with vesicles from the TGN ultimately into lysosomes.

some cancer cells are highly dependent on glycolysis for ATP production.

proto-eukaryotes were anaerobic and the presence of mitochondria allowed them to be aerobic.

inverting the orientation of the transporter proteins in the membrane.

appears to be important for cancer cells becoming metastatic.

Nothing would change; this is the normal Ran-GAP and Ran-GEF distribution.

QUESTION 3 Zoë must acquire a business phone. She got the following mobile phone rates at Cell Zone. Answer the questions  that follow by referring to the table below:   Cell Zone’s two business options:   Name Cell Z Busy Ness Cell Z Bizniz Type Contract Pay per minute Fixed cost R100 None Free minutes 150 minutes None Cost per minute R1.20 R1.00           3.1 Write down a formula to work out the cost for Cell Z Busy Ness. (4) 3.2 Write down a formula to work out the cost for Cell Z Bizniz. (2) 3.3 Set up a table to compare the cost of the two options. Use the table below as a guide. (6)   Total min 0 100 200 300 400 500 Busy Ness             Bizniz               3.4  If Zoë on average phones 200 and 300 minutes a month, which one of the two options should she choose? (2)

continue to pump ions and to hydrolyze ATP, but only generate heat in the process.