Q12 - Osmolarity, Not Volume, Dominates Fast Kidney Responses
Ernest Verney (1894-1967) explained the regulation of urine production. At the indicated time, dogs (Canis lupus familiaris) were given equal volumes of fresh water, or salty water of the same concentration (osmolarity) as blood, orally or through jugular injection. The volume of urine generated was measured with a catheter.
Using the information and data, determine which of the statements are true or which are false.
A. Blood volume is adjusted more quickly than blood osmolarity.
B. Blood osmolarity receptors are the dominant regulators of urine production.
C. Receptors in the gastrointestinal tract regulate the kidneys.
D. Urine at time X has a higher osmolarity than urine at time Y.
Question reproduced from IBO 2017, Theoretical Exam B, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF · Official answer key & worked solutions