ATI Pathophysiology Practice Exam

Which section of the nephron is located closest to the collecting duct?

1. Proximal convoluted tubule

2. Loop of Henle

3. Distal convoluted tubule

4. Glomerulus

The correct answer is: Distal convoluted tubule

The distal convoluted tubule is the part of the nephron that is situated closest to the collecting duct. After filtrate passes through the proximal convoluted tubule and the loop of Henle, it enters the distal convoluted tubule. This section plays a critical role in the final adjustment of the filtrate composition, including the regulation of electrolyte balance and the reabsorption of water. As the filtrate moves from the distal convoluted tubule, it is directed into the collecting duct, where further water reabsorption takes place under the influence of hormones like antidiuretic hormone (ADH). The anatomical proximity of the distal convoluted tubule to the collecting duct is significant in maintaining the homeostasis of fluid and electrolyte balance in the body.