Here’s a question: If you lost your nose, would you still be able to smell? Believe it or not, the answer is yes! Even though the nose is the organ of smell, it’s only the outside part. There’s an inside part that you can’t see. That’s where the smelling gets done.
There are all kinds of noses in the animal world: big or small, flat or round, and long or short. In people, what we call the nose is the formation of bone, cartilage (tough tissue), and skin on the front of the face.
Your skin is your body’s largest organ, larger than your heart or lungs or brain. Skin covers your whole body, from the top of your head to the soles of your feet. You could not live without your skin. Skin keeps germs and other harmful things out of your body. It keeps water, blood, and other fluids that you need inside your body.
You are always losing your skin and growing new skin. The outside layer of your skin is dead. It flakes off all the time. New skin grows to replace it.
LAYERS OF SKIN
Your skin has an outside layer called the epidermis. Under that is a layer called the dermis. Under those two layers is a layer of fat.
They can bite, chomp, chew, crush, nibble, and gnaw. They can be cleaned, crowned, drilled, filled, pulled, capped, and straightened. You can crack them, break them, brush them, and floss them. You can even replace them if you lose them. What are they?
They’re your teeth.
WHAT TEETH ARE
Teeth are the hardest parts of the human body. They often survive long after the bones, or skeleton, have decayed. Scientists have discovered ancient teeth from animals and humans.
Smoking is “hateful to the nose, harmful to the brain, and dangerous to the lungs.” This was the view of England’s king James I in 1604. For long afterward, smoking was considered harmless. Today, more and more people agree with King James.
TOBACCO AND NICOTINE
Smoking means breathing the smoke of burning tobacco leaves. Tobacco is a plant.
Tobacco is processed for smoking in different ways. People smoke tobacco in pipes, cigars, and cigarettes.
When you wake up with the sniffles not feeling too well, you probably have a cold. Colds are caused by viruses. Other viruses cause the flu and some very serious illnesses such as chicken pox, measles, rabies, and AIDS. Scientists think viruses might also be a cause of some cancers. Many viruses can go from one person to another.
A TINY GERM
A virus is a tiny germ that can infect the body. Different kinds of viruses can also infect animals and plants. There are thousands of kinds of viruses. There are about 100 kinds of viruses that cause colds.