Ion Flux Through Membranes

Question 1

A small Biotech company in Boston recently created a more potent version of digoxin for treating patients with congestive heart failure. Which of the following is the direct protein target to which this drug binds to in order to exert its effect on cardiomyocytes?
A. Sodium calcium exchanger
B. Sodium potassium ATPase
C. Sodium channel
D. Calcium ATPase
E. Calcium channel

Answer 1

B. Sodium potassium ATPase

Question 2

A 16-year-old boy was brought to the ER by his mother due to severe abdominal pain. She told the physician that the pain seemed to come in waves. Ultrasound of the abdomen revealed kidney stones. After further testing a diagnosis of cystinuria was made. Transport of which amino acid is defective in this condition?
A. Cysteine
B. Cystine
C. Glycine
D. Histidine
E. Methionine

Answer 2

B. Cystine