How do the kidneys filter the blood?
1 Answer
Kidneys filter blood and in the process remove wastes and excess substances to produce urine.
Explanation:
The functional unit of the kidney is the nephron . Nephron is a long fine tubule which is folded into a cup like structure called Bowman's capsule. This capsule encloses a ball like cluster of fine capillaries, which is called the glomerulus.
Blood enters from one end and leaves from the other end passing through tiny arterioles in the glomerulus. Cells, proteins and other large molecules are filtered out of the glomerulus by a process of ultrafiltration. The left over ultrafiltrate resembles plasma, but has negligible plasma proteins.
The ultrafiltrate enters the Bowman's space and flows into the tubules of the nephron. The composition of this filterate is altered in the tubule. Certain substances are secreted into it and selective reabsorption of water and other constituents also occurs.
The collecting tubules transport the urine thus formed into the ureter.
