Question

What do we mean by saying that PCT in nephron absorb water and electrolytes . Does that mean thay are absorbedand pass into blood or simply absorb by walls of PCT ?

Answer 1

The Proximal convoluted tubule(PCT) is the highly twisted part of the nephron that occurs immediately after the glomerulus.

After active absorption of filtrates in the glomerulus( the word 'active' refers to the use of ATP as an external source of energy for the required action to be performed), the only remaining substrates left are water and electrolytes.

This water and electrolytes are 'selectively ' reabsorbed by the PCT into itself which later goes and mixes with the blood.

The word 'selectively' means that this process of reabsorption does not ALWAYS happen - It is reabsorbed only if there is less of these constituents.

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