Read the following functions and identify the part of nephron responsible for it. A. Nearly all of the essential nutrients and 70-80% of electrolytes and water are reabsorbed by this segment. B. Conditional reabsorption of N a+ and water takes place in this segment. C. Large amounts of water could be reabsorbed from this region to produce concentrated urine.

Question

Read the following functions and identify the part of nephron responsible for it. A. Nearly all of the essential nutrients and 70-80% of electrolytes and water are reabsorbed by this segment. B. Conditional reabsorption of N a+ and water takes place in this segment. C. Large amounts of water could be reabsorbed from this region to produce concentrated urine. (A) Loop of Henle (B) Collecting duct (C) Collecting duct (D) Loop of Henle

Tardigrade Admin · Accepted Answer

A. Functions of Proximal Convoluted Tubule (PCT)

1.

PCT absorbs almost all essential nutrients.

2.

PCT absorbs about 70-80 % electrolytes and water.

3.

As PCT selectively secretes H+ ions, ammonia and potassium ions into the filtrate and also absorbs

H C O_{3}^{-}

from it, it maintains the pH and ionic balance of the body fluids.
B. Functions of Henle's Loop

1.

Maintenance of high osmolarity of medullary interstitial fluid.

2.

Reabsorption to some extent (some water and electrolytes enter medullary fluid).
C. Functions of Distal Convoluted Tubule (DCT)

1.

Conditional reabsorption of

N a^{+}

and water.

2.

Reabsorption of

H C O_{3}^{-}

and selective secretion of

H^{+}, K^{+,}

and

N H_{3}

for maintaining the pH and sodium-potassium balance in the blood.
D. Functions of Collecting Duct

1.

Reabsorbed of large amounts of water resulting in the production of concentrated urine.

2.

Small amounts of urea enter the medullary interstitium to keep up the osmolarity.

3.

By the selective secretion of

H^{+}

and

K^{+}

ions, collecting ducts also plays an important role in the maintenance of pH and ionic balance of the blood.