Which of these statements about proximal convoluted tubule is/are true? I. It is lined by simple columnar brush border epithelium which increases the surface area for reabsorption. II. Nearly all of the essential nutrients and 70%-80% of electrolytes and water are reabsorbed by this segment. III. It selectively secretes hydrogen ions, ammonia and potassium ions into the filtrate. IV. It is the most convoluted part of the nephron and is present in the medullary region of the kidney.

Question

Which of these statements about proximal convoluted tubule is/are true? I. It is lined by simple columnar brush border epithelium which increases the surface area for reabsorption. II. Nearly all of the essential nutrients and 70%-80% of electrolytes and water are reabsorbed by this segment. III. It selectively secretes hydrogen ions, ammonia and potassium ions into the filtrate. IV. It is the most convoluted part of the nephron and is present in the medullary region of the kidney. (A) I and IV (B) I, II and III (C) II and III (D) I, II, III and IV

Tardigrade Admin · Accepted Answer

Proximal convoluted tubule or PCT is the most convoluted part of the nephron located in the renal cortex. It is the first part of the renal tube and is internally lined by simple cuboidal brush border epithelium, which increases the surface area for reabsorption. There is maximum reabsorption of nutrients, electrolytes and water in this region of the nephron. It also maintains the pH by tubular secretion of hydrogen ions, ammonia and potassium ions.