Meet the Nephron!
Meet the
nephron. This is Dr. Steven Andrew
Davis, Speaking of Health. Multiple
choice: Is a nephron a visitor from the
star “Nephros”; the nephew of a nephew; or the functional unit of
the kidney? Of course, it’s the
kidney -- you know the specialty of the nephrologist. There are thousands of such doctors, but
there are millions of nephrons in each of our kidneys. These nephrons dispose of unwanted products
of our metabolism, the breakdown products of protein and remnants of drugs.
There’s also
the delicate balance of minerals in the blood stream that makes life
possible. The nephrons do this too, and
it all starts with a biologic filter called the glomerulus. This is plexus of tissue that holds blood
cells behind while fluids and waste pass through. But it’s not a simple sieve. The fluid takes a journey through tiny
microscopic tubules, living pipes lined by cells that survey the fluid as it
passes by and bring some of it back into the circulation. This means that fluid and waste on its way
out of the body is looked at again and some of the minerals are reabsorbed
– because the body needs them.
Normally, a lot of
the salt and some of the water is kept in the body, and some minerals are even
exchanged for others by the tubules.
What’s left after this eventually passes into larger collecting
pipes and eventually exits the body as urine.
The biology is
complex, but the concept is simple.
Millions of tine units work together to filter out wastes then
re-examine its contents and take back what the body needs. Speaking of Health, I’m Dr.
Steven Andrew Davis for CBS News.
E-Mail
drdavis@davishealth.com
Dr. Steve Davis
7810 Louis Pasteur #200
210/614-3355
