What is the primary function of the distal convoluted tubule in the nephron?

The primary function of the distal convoluted tubule (DCT) in the nephron is indeed related to the reabsorption of salts, particularly sodium and chloride ions. This segment of the nephron plays a crucial role in the regulation of electrolytes and is involved in several important processes related to homeostasis.

In the DCT, sodium is actively reabsorbed from the tubular fluid into the blood, which contributes to the maintenance of sodium balance and blood pressure regulation. The reabsorption of chloride often follows passively along with sodium due to electrochemical gradients. The DCT also has a role in the fine-tuning of electrolyte balance and is influenced by hormones such as aldosterone, which promotes sodium reabsorption and potassium secretion.

While the DCT does involve some water reabsorption, this occurs to a lesser extent compared to other parts of the nephron, such as the proximal convoluted tubule and the loop of Henle, which have more significant roles in water reabsorption. Filtration of blood primarily takes place at the glomerulus before the filtrate enters the nephron; thus, the DCT is not involved in this process. The concentration of urine is mainly a function of the loop of Henle