167.HOW DO OUR KIDNEYS FUNCTION?
The kidneys, two flat, bean-shaped, solid organs, are among the most important in our body. About 10 centimeters, they lie on each side of the spine near the waistline.
The kidneys remove unwanted substances from the body. It is just as important for the body to get rid of what it doesn’t need and can’t use as it is for it to take in what it needs. They also regulate the amount of water and other substances in the blood.
166.HOW DO ARTERIES DIFFER FROM VEINS?
There is no transportation system in any city that can compare in efficiency with the circulatory system of the body.
If you will imagine two systems of pipes, one large and one small, both meeting at a central pumping station, you’ll have an idea of the circulatory system. The smaller system of pipes goes from the heart to the lungs and back. The larger one goes from the heart to the various other parts of the body.
165.WHY DO CATFISH HAVE WHISKERS?
A catfish might say to you: “why do you call them ‘whiskers?’ They are not whiskers at all!” And, of course, it’s only because those things on the fish’s mouth resemble a cat’s whiskers that we call them that. Actually they are barbels, or feelers, and help the catfish know what’s going on all about him.
There’s another way a catfish is supposed to resemble a cat: makes a buzzing or croaking sound when caught that suggests a cat’s purring. It’s for these two reasons that this kind of fish got its name “catfish.”
