Question

Number of mitochondria is maximum in part of uriniferous tubule
A. PCT
B. Loop of Henle
C. DCT
D. Bowman’s capsule

Answer 1

Hint: Mitochondria is also known as a powerhouse of the cell due to its ability to produce energy in the form of ATP. uriniferous tubules are the tubular part of nephron. Nephron is the structural and functional unit of the kidney. These tubules help to remove waste and undigested material out of our body. They play a major role in the process of excretion.

Complete answer:
Lower part of Bowman's capsule leads into PCT (Proximal Convoluted Tubule). The latter is present in the cortex. It is highly coiled and surrounded by peritubular blood capillaries, PCT is lined by cuboidal epithelium having brush borders with long microvilli for increasing absorptive area. The cells contain abundant mitochondria and food reserve for providing energy to perform active absorption and secretion.

Now let us match this with the given options:
PCT: This region performs a function of absorption and secretion which requires a large amount of energy. The energy is provided by mitochondria. Thus this option is correct.

Loop of Henle: It is a tubular part of nephron which descends into renal medulla and does not perform secretion and absorption thus does not require mitochondria. So, this option is not correct.

DCT: It maintains pH and sodium potassium balance in blood which do not require large amounts of energy. thus do not require mitochondria. So, this option is not correct.

Bowman’s capsule: It does not perform secretion and absorption thus does not require mitochondria. So, this option is not correct.

Hence, the correct answer is option (A).

Note: Proximal convoluted tubule (PCT)
It is lined by a simple cuboidal brush border epithelium which increases the surface area for reabsorption. Nearly all of the essential nutrients, and 70-80% of electrolytes and water are reabsorbed by this segment. PCT also helps to maintain the pH and ionic balance of the body fluids by selective secretion of hydrogen ions and ammonia into the filtrate.