Answer to Question 1
Ans: B
Feedback:
When antidiuretic hormone is present, the distal tubule of the nephron becomes more permeable to water. This causes the renal system to retain more water. A lack of antidiuretic hormone causes increased production of dilute urine. Antidiuretic hormone does not cause thirst.
Answer to Question 2
Ans: A
Feedback:
The process of filtration begins at the glomerulus.