Answer to Question 1
Correct Answer: 1,2,3
Rationale 1: Renin is an enzyme that is synthesized, stored, and secreted by specialized cells in the kidney known as juxtaglomerular (JG) cells.
Rationale 2: The macula densa recognizes the slow flow rate (and less sodium) and sends a chemical message to the JG cells to release more renin.
Rationale 3: The activation of the sympathetic nervous system controls the release of renin.
Rationale 4: The parasympathetic nervous system does not control the release of renin.
Rationale 5: The cardiovascular system does not control the release of renin.
Global Rationale: Renin is an enzyme that is synthesized, stored, and secreted by specialized cells in the kidney known as juxtaglomerular (JG) cells. The macula densa recognizes the slow flow rate (and less sodium) and sends a chemical message to the JG cells to release more renin. The activation of the sympathetic nervous system controls the release of renin. The parasympathetic nervous system and the cardiovascular system do not control the release of renin.
Answer to Question 2
Correct Answer: 1
Rationale 1: Lowered blood pressure causes the kidney to release renin.
Rationale 2: Renin secretion is turned on by loss of blood volume, not by decreased cardiac output.
Rationale 3: Increased blood pressure turns off renin secretion.
Rationale 4: Increased blood pressure turns off renin secretion.
Global Rationale: Lowered blood pressure causes the kidney to release renin. Renin secretion is turned on by loss of blood volume, not by decreased cardiac output. Increased blood pressure turns off renin secretion.