Question

In the kidney, the formation of urine involves the following processes

• A. Glomerular filtration, reabsorption and tubular secretion
• B. Reabsorption and filtration
• C. Secretion and absorption
• D. None of the above

Answer 1

The correct option is A Glomerular filtration, reabsorption and tubular secretion

Urine is mainly formed in the kidney. The amino acid is deaminated to form urea in the liver by ornithine cycle which is further filtered by the kidney. Urine is formed by the following three steps namely, glomerular filtration, reabsorption, and secretion, that takes place in different parts of the nephron. The first step in urine formation is the filtration of blood, which is carried out by the glomerulus and is called glomerular filtration. The tubular epithelial cells in different segments of nephron perform absorption (reabsorption) either by active or passive mechanisms. Tubular secretion is also an important step in urine formation as it helps in the maintenance of an ionic and acid-base balance of body fluids.

So, the correct answer is option A.