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We
all learned about the human body in school. We read some
popular science books. Some of us took biology classes or
anatomy as a major. We had teachers referring to the human
body as an incredible machine. Students admire the heart, the
muscle relentlessly pumping blood 60-100 times a minute for a
lifetime. Our eyes, constructed like a sophisticated camera
fascinate us.
Somehow,
probably because sex, urination, and defecation are taboo
subjects, we all ignore how important the pelvic
floor is and the lower
urinary system it supports. Only when something
goes wrong do we start to appreciate how
that pelvic
floor and bladder served
us well without our having paid any attention to its functions
till then.
Our
urinary system is designed to enable us to keep our fluids and
salts
(or electrolytes)
at relatively constant levels. To do so, the
kidneys, a pair of fist-size organs, filter our blood
constantly, but these are not like
the ordinary filtering systems that we are used to
seeing. Kidney filtering is not based solely on the size
of the particles like our kitchen strainer or the air or
fuel filters in our cars, but also on their chemical makeup (entity)
or configuration. The kidneys are equipped with special
elements called receptors
able to identify different salt particles and other
blood constitutes. The receptors can then facilitate the
elimination of certain particles into the urine as a waste
product or help in keeping them as a valuable asset for the
body to use. The filtered urine and its constitutes
then flows through a collecting system and will eventually be excreted by the body.
To
get a better grasp of how this collecting system is designed,
look at Figure 1 (image on the left - click on graphic to see a
larger image- Illustration
by Florence Adar). You will see a sketch of two rivers flowing
toward a large body of water—a reservoir created by a gated
dam. Water reaching the reservoir is slowly collected but can
be emptied once the gate is open.
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