Question

Give reason for the following
Reabsorption is called as selective reabsorption.

Answer 1

Glomerular filtrate:

1. The glomerular filtrate reaches the renal tubule as a dilute solution in the second step of urine production, and various components present in the filtrate are reabsorbed.
2. Resorption occurs when some of the components in the filtrate are reabsorbed to the extent of $99\%$.

Selective reabsorption:

1. As the filtrate passes through the tubule, some water is reabsorbed, along with other beneficial chemicals like salts, amino acids, glucose, and so on, to the extent that it does not change the blood's normal concentration.
2. Movements into and out of epithelial cells in different segments of the nephron are either passive or active, depending on the sorts of molecules being reabsorbed.
3. Only a few substances, such as glucose and some salts, are reabsorbed in the renal tubule.
4. As a result, it's known as selective reabsorption.