Q30 - Localizing an Insulin-Signaling Defect from Binding and Glucose-Clearance Tests
Figure Q.30A shows insulin secretion and the mechanism by which insulin stimulates glucose absorption into a cell. The mechanism includes four steps depicted by the four circled digits 1 to 4. Four patients (E, F, G and H) had a defect each in a single step of the above mechanism. Patients E, F, G and H had defects in steps 1, 2, 3 and 4, respectively. These patients were given two tests:
- Test 1: Muscle cells from each patient were isolated and the percentage of insulin binding cells at different concentrations of insulin was determined (Figure Q.30B).
- Test 2: Each patient was injected with the same insulin quantity relative to their body mass and their plasma glucose concentrations were then measured at various times after injection (Figure Q.30C).
Figure 1.
Using the information and data, determine which of the statements are true or which are false.
A. The result of Test 1 of Patient G could be shown in Line 1.
B. Lines 2 and 3 show the results of Tests 1 and 2, respectively, of Patient F.
C. Line 3 shows the tested result of Patient E.
D. Lines 1 and 4 show the results of Tests 1 and 2, respectively, of Patient H.
Question reproduced from IBO 2016, Theoretical Paper A, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF · Community solutions (unofficial)