What is glomerular filtration rate (GFR) and why is it important?

Prepare for the Anatomy and Physiology II Milestone 1 Test with engaging questions, in-depth explanations, and focused study resources. Start your journey to excel in your exam!

Multiple Choice

What is glomerular filtration rate (GFR) and why is it important?

GFR is the rate at which filtrate is produced by the glomeruli each minute. It reflects how well the kidneys are filtering plasma and thereby maintaining fluid and electrolyte balance and removing wastes. In a healthy person, GFR is about 125 mL/min (roughly 180 L of filtrate per day). Keeping this filtration rate up is essential for maintaining proper electrolyte levels, acid-base balance, and waste clearance; when GFR falls, waste builds up and fluid/electrolyte homeostasis can be disrupted. Clinically, GFR is used to assess kidney function, stage kidney disease, and guide dosing for drugs cleared by the kidneys. It’s commonly estimated from serum creatinine (eGFR). RBC production is regulated by erythropoietin and occurs in the bone marrow, not a measure of kidney filtration. The total blood flow through the kidneys pertains to renal perfusion, not how much filtrate is formed. The rate of urine formation in the collecting ducts refers to final urine output, which depends on filtration plus tubular reabsorption and secretion; it is downstream of what GFR measures.

GFR is the rate at which filtrate is produced by the glomeruli each minute. It reflects how well the kidneys are filtering plasma and thereby maintaining fluid and electrolyte balance and removing wastes. In a healthy person, GFR is about 125 mL/min (roughly 180 L of filtrate per day). Keeping this filtration rate up is essential for maintaining proper electrolyte levels, acid-base balance, and waste clearance; when GFR falls, waste builds up and fluid/electrolyte homeostasis can be disrupted. Clinically, GFR is used to assess kidney function, stage kidney disease, and guide dosing for drugs cleared by the kidneys. It’s commonly estimated from serum creatinine (eGFR).

RBC production is regulated by erythropoietin and occurs in the bone marrow, not a measure of kidney filtration. The total blood flow through the kidneys pertains to renal perfusion, not how much filtrate is formed. The rate of urine formation in the collecting ducts refers to final urine output, which depends on filtration plus tubular reabsorption and secretion; it is downstream of what GFR measures.

More practice questions