Kaplan Nursing Entrance Practice Exam

Which component of the nephron is responsible for filtration?

1. Glomerulus

2. Proximal tubule

3. Loop of Henle

4. Distal convoluted tubule

The correct answer is: Glomerulus

The glomerulus is the key component of the nephron responsible for filtration. It is a network of capillaries encased in a structure called Bowman's capsule. In this area, blood is filtered as it passes through the glomerular capillaries. The high-pressure environment within the glomerulus promotes the movement of water, electrolytes, and small molecules from the blood into the Bowman's capsule, creating a filtrate that will eventually become urine. This process is crucial as it removes waste products and excess substances from the bloodstream, contributing to the regulation of body fluid composition. The other components of the nephron, such as the proximal tubule, loop of Henle, and distal convoluted tubule, primarily involve the reabsorption of important substances and secretion of waste products but do not play a direct role in the initial filtration process.