Distal Convoluted Tubule

Definition

The distal convoluted tubule is a segment of the nephron, the functional unit of the kidney, located between the loop of Henle and the collecting duct. It plays a crucial role in the kidney's ability to regulate fluid volume and composition within the body.

5 Must Know Facts For Your Next Test

1. The distal convoluted tubule is responsible for the final adjustments to the composition of the filtrate before it enters the collecting duct.
2. It is the site of active reabsorption and secretion of various substances, including sodium, potassium, and hydrogen ions.
3. The distal convoluted tubule plays a key role in the regulation of fluid volume and electrolyte balance through its responsiveness to hormones such as aldosterone and antidiuretic hormone (ADH).
4. The distal convoluted tubule is the primary site of action for diuretic drugs, which work by inhibiting the reabsorption of substances in this segment.
5. Anatomically, the distal convoluted tubule is located in the renal cortex, adjacent to the renal corpuscle and the juxtaglomerular apparatus.

Review Questions

• Describe the role of the distal convoluted tubule in the gross anatomy of the kidney.
  • The distal convoluted tubule is a crucial component of the nephron, the functional unit of the kidney. It is located in the renal cortex, positioned between the loop of Henle and the collecting duct. This strategic location allows the distal convoluted tubule to play a key role in the kidney's ability to regulate fluid volume and composition by facilitating the final adjustments to the filtrate before it enters the collecting duct.
• Explain the importance of the distal convoluted tubule in the microscopic anatomy of the kidney and its role in tubular reabsorption.
  • At the microscopic level, the distal convoluted tubule is responsible for the active reabsorption and secretion of various substances, including sodium, potassium, and hydrogen ions. This fine-tuning of the filtrate composition is crucial for maintaining fluid volume and electrolyte balance within the body. The distal convoluted tubule's responsiveness to hormones, such as aldosterone and antidiuretic hormone (ADH), further enhances its role in regulating fluid volume and composition.
• Analyze the significance of the distal convoluted tubule in the regulation of fluid volume and composition, and how this relates to the overall function of the kidney.
  • The distal convoluted tubule plays a pivotal role in the kidney's ability to regulate fluid volume and composition within the body. By actively reabsorbing and secreting various substances, the distal convoluted tubule ensures that the final urine composition is tailored to the body's needs. This regulation of fluid volume and electrolyte balance is essential for maintaining homeostasis and supporting the overall physiological functions of the body. The distal convoluted tubule's responsiveness to hormones, such as aldosterone and ADH, further enhances its role in this critical process, making it a key component in the kidney's complex system of filtration, reabsorption, and secretion.

Related terms

Nephron:

The functional unit of the kidney, consisting of the renal corpuscle, proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct.

Proximal Convoluted Tubule: The first segment of the nephron, responsible for the reabsorption of the majority of filtered substances, including water, glucose, amino acids, and ions.

Loop of Henle:

The U-shaped portion of the nephron that extends from the proximal convoluted tubule and is involved in the kidney's ability to concentrate urine.