Clearance tests used to determine the glomerular filtration rate must measure substances that are:
A) Not filtered by the glomerulus
B) Completely reabsorbed by the proximal convoluted tubule
C) Secreted in the distal convoluted tubule
D) Neither reabsorbed or secreted by the tubules

Question

Quizplus · Accepted Answer

Clearance tests are used to measure the filtration capacity of the glomerulus. Substances that are neither reabsorbed nor secreted by the tubules provide the most accurate measure of glomerular filtration rate. Examples of such substances include inulin, creatinine, and urea. Choice A and B are incorrect because substances that are not filtered at all or completely reabsorbed do not provide an accurate measure of filtration rate. Choice C is incorrect because substances that are secreted in the distal convoluted tubule are not solely a measure of glomerular filtration rate.

Clearance Tests Used to Determine the Glomerular Filtration Rate Must