|Life Science||Anatomy 4G2.00||Science In Society||Personal Needs 4.2 ab|
CONTENT STANDARD: Life Science
CONTENT TOPIC: Anatomy
CONCEPT: The human body is composed of sensory organs which detect heat, light, and sound.
CONTENT OBJECTIVE: 4G2.00 To understand the proper care of sensory organs
INSTRUCTIONAL OBJECTIVE: The learner will:
TN COMPONENT OF SCIENCE: Science In Society
BENCHMARK: People use and contribute to science to improve their lives.
4.2b Science concepts may be applied to personal decisions.
BENCHMARK: Individual behavior may be influenced by an understanding of science concepts
Another way people can avoid injuring their ears is by protecting their ears from loud noises. What is noise? (response) You may recall that when sound waves strike the eardrum, they cause the eardrum to vibrate. When sound waves from something making a soft sound strike the eardrum, the eardrum vibrates with slight force. But when sound waves from something making a loud sound strike the eardrum, the eardrum vibrates with great force. The loud sound waves can cause the eardrum to vibrate with so great a force that the eardrum tears. How might that effect a person's hearing? (response) Explain your answers. (response)
Besides the eardrum, certain other parts of the ear can be affected by noise. Those parts are the nerve cells sensitive to sound vibrations. Each cell of your body carries out its activities most efficiently when you are at rest. The nerve cells within your ears, like all the other cells of your body, also tire. But the nerve cells within the ears tire quickly when sound waves are very loud or continue for an extended period of time. When either situation occurs, the tired nerve cells within the ears tend to send fewer impulses than normal to the brain, causing a temporary loss of a certain amount of hearing.
Have you ever noticed that when you have a cold, you sometimes cannot hear as well as you normally do? The reason a cold sometimes affects a person's hearing is that it often affects the air pressure in the middle ear.
Air always presses against the body, including the outer side of the eardrum. But vibrate normally, the air pressure against the inner side of the eardrum must be the same as that against the outer side. Keeping the air pressure against the inner side of the eardrum equal to the pressure against the outside of the eardrum is the function of a small tube, the Eustachian tube.
The Eustachian tube extends from the throat to the middle ear. Normally, air moves in and out of that tube, keeping the pressure against the inner and outer side of the eardrum equal. But when you have a cold, mucus and swelling caused by the irritation of the germs tend to close off the Eustachian tube. That keeps air from moving in or out of the middle ear, causing the air pressure against the inner side of the eardrum to be different from the air pressure against the outer side of the eardrum. Moreover, when you blow your nose, some of the mucus and the germs can easily be forced up through the Eustachian tube to the middle ear. If those germs reach the middle ear, they cause a middle ear infection. How might you help avoid such an infection? (response)
Still another way people can help care for their ears is by having their ears examined regularly. A doctor who specializes in problem of the ear is called an Otologist. Might people benefit from having their hearing tested regularly, even though the results of those tests may show that their level of hearing is normal? (response) Why or why not? (response)
This Classroom Connector addresses Instructional Objective 2.02.
Another way you can help care for your eyes is to have your eyes examined regularly by a doctor who is specially trained to care for the eyes. An Ophthalmologist is a physician, or doctor, who specializes in the diagnosis and the treatment of eye problems through the use of medicines, surgery, or corrective lenses. Another doctor specially trained to care for the eyes is called an optometrist. An optometrist is a doctor who treats certain eye problems through the use of eye exercises and corrective lenses. Why would having your eyes examined regularly by a doctor be a way you can help care for them? (response)
Air pollution affects many organs of the body. Two of those organs are the eyes. Some of the pollutants in air that affect the eyes are gases. One of those gases is carbon monoxide.
Carbon monoxide is found mainly in the exhaust fumes of automobiles and in tobacco smoke. When breathed in, carbon monoxide is picked up by the blood more easily than oxygen. As a result, when a person breathes air containing carbon monoxide, less oxygen than normal can be picked up by the blood and carried to each cell of the person's body. When the cells of a person's body receive less oxygen than normal, the cells cannot carry out their activities as efficiently as they should. Since the eyes are made up of cells, those cells are also affected when they do not receive the normal supply of oxygen. How might that affect a person's vision? (response)
Besides carbon monoxide, there are certain other gases that contribute to air pollution and that affect the eyes. Those gases include sulfur oxides, which come mainly from the burning of fuels such as oil and coal; and hydrocarbons, which come mainly from the burning of gasoline. When these gases come in contact with the eyes, the gases irritate the eyes, causing the eyes to tear excessively and to burn. Do you think constant irritation of the eyes by these gases might be harmful to the eyes? (response)
There are some problems of the eyes that you cannot prevent. These include far-sightedness, near-sightedness, astigmatism, and color blindness.
Your eyes are valuable tools. They deserve the best care you can give them. An important part of such care is being aware of changes in the way your eyes function and doing something about them.
Seek medical treatment if you develop one or more of these symptoms: loss of sight; blurred or hazy vision; seeing halos around lights; seeing flashes of lights even when your eyes are closed; loss of side vision; severe or repeated headaches; frequent squinting or frowning; double vision; loss of normal night vision; reddened, burning, itching, or painful eyes; or crusting of the eyelids.
This Classroom Connector addresses Instructional Objective 2.03.
The skin has two layers. The inner layer, called the dermis, is made of living cells. The health of this inner layer depends on oxygen and nutrients brought to it by circulating blood. The outer layer of skin is called the epidermis. Dead cells at the top of the epidermis are continually being scaled off and replaced by cells from below.
The health of the epidermis depends largely on cleanliness. A general rule for keeping the skin clean is to wash it at least once a day with soap and water. Yet there are times when this general routine is not enough. Sometimes, special problems arise that require special care. Some of these problems are: dry and oily skin; acne; body odor; fungal infections; sunburn; and skin cancer.
The amount of moisture in your skin has a lot to do with how it looks and feels. When the skin on your hands or other areas is too dry, it may feel tight, sore, rough, and flaky. Dry skin may even crack and bleed. Dry skin can be the result of exposure to wind, cold, or sun. It can be caused by use of soap or detergents, frequent swimming or low humidity.
Emollients, such as bath oil and body lotions are products designed to soften and soothe skin. Emollients may be used to relieve dryness. However, you should choose such products carefully and recognize their limitations. Consult a physician if a dry skin problem seems major. Flaking and bleeding skin can be signs of more serious conditions.
Oily skin may occur for many reasons. A common reason during adolescence is that certain changes in your body cause the oil glands to produce more oil. Such things are heredity, emotions, and temperature also may be factors in producing oily skin.
A product applied to the skin cannot stop the production of oil. However, an excess can be removed from the skin surface. If you have oily areas, it helps to wash them at least twice a day. Oily cosmetics should be avoided.
Acne consists of whiteheads, blackheads, and pimples. It commonly occurs on the face and other oily areas. Severe acne can lead to permanent scarring. However, many who have acne suffer more emotionally than physically. Acne can affect self-confidence and happiness. Unfortunately, there is no cure for acne. Treatment is aimed at preventing scars and reducing the severity of the outbreak.
Perspiration is a natural function that aids in cooling and in removing wastes from the body. However, the same changes in hormones that can cause acne in adolescence also can cause enlargement and over activity of the sweat glands. Perspiration itself is odorless, but the bacteria that are always present on the skin cause the perspiration to develop an unpleasant odor.
Body odor can be controlled, chiefly by keeping ourselves clean. Daily washing with soap and water will get rid of some bacteria on your skin. Because your clothing may pick up some odor from your body, it also is important to wear clean clothes every day.
Fungal infections are caused by fungi. They appear on various areas of the body and can spread from one area of the body to another or from one person to another. Fungi need a moist place in which to live. So it is important to dry your feet well especially between the toes after you wash. Athlete's foot is a fungal infection on the feet. Change your socks or stockings often if you are active physically or if your feet perspire heavily.
Because the sun is an important source of energy for the earth, you probably do not view it as an enemy. Yet overexposure to sunlight damages your skin. Sunlight includes both ultraviolet and infrared radiation. Ultraviolet radiation causes sunburn; infrared radiation does not. Infrared radiation has a warming effect. You feel it as heat. On a cloudy day, less infrared radiation reaches you than on a clear day. Therefore, you may stay outside longer than usual. You may not realize that ultraviolet radiation still is reaching your skin. This can result in sunburn, just as staying out too long on a sunny day would do. Reflection of sunlight from sand, water, or snow increases your exposure to ultraviolet radiation. You may have experienced sunburn. Did you know that sunburn is the same as other burns? (response) In a first degree sunburn, the skin is reddened. In a second-degree sunburn, blisters form. Both sunburns are painful, but a second-degree burn carries the danger of infection.
Even if you avoid sunburn, overexposure to sunlight over the years can cause the skin to prematurely develop a leathery texture, with wrinkles, folds, and sags. This is because the skin loses elasticity as a result of exposure to the sun.
A number of skin problems, such as cold sores, can be aggravated by sunlight. But the most alarming connection between sunlight and disease involves skin cancer. There is evidence that suggests that repeated and persistent exposure to sunlight may be one of the major factors in causing skin cancer in some people. Skin cancer has long been an occupational hazard for farmers, sailors, and ranchers, who are outdoors much of the time. Skin cancer is most common in the United States in the southern and southwestern parts where people are exposed to more sunlight than people in northern areas. Skin cancer usually appears on exposed areas of the body such as the face and hands.
If you need or want to be in the sun, gradual and moderate exposure is the best for both skin care and tanning. Among other things, too much exposure causes the skin to peel, therefore losing some of the tan already acquired. You should use suntan products. The chemicals are known as sun screens. These chemicals absorb some of the sun's ultraviolet radiation.
|Minutes of Exposure||Any time thereafter, judge on basis of tenderness or redness|
This Classroom Connector addresses Instructional Objective 2.04.
1. Warms the air
2. Cleans the air (because of mucus and hairs)
3. Adds moisture to the air (because of mucus)
The cells that line your nose and sinuses make a liquid called mucus. Mucus traps dirt and dust. It also keeps your sinuses and the air you inhale moist. Sometimes too much mucus is made. You will have clogged nasal passages when you have a cold. The proper way to blow a clogged nose is to hold the handkerchief tightly, an infection from the nose can travel to the middle ear. Never insert or place an object in the nostrils to get rid of mucus. This can cause a blood vessel to burst. You may get a bloody nose.
The nose can also be examined by a doctor. The doctor will use an instrument called a rhinoscope. The instrument enables the doctor to look at the condition of the lining of the nose. An inflamed, or reddened, lining of the nose may indicate an infection or an allergy, either of which could not only decrease a person's sense of smell but also make breathing difficult.
This Classroom Connector addresses Instructional Objective 2.05.
The sensory organs are highly specialized. Sensory nerves carry impulses from the senses to the brain. Proper health care is a must to ensure the protection of your sense organs. Be careful with food or drink that is too hot. Food that is too hot will burn the tongue.
The tongue may also be checked by a doctor. The doctor checks the tongue and lining of the mouth for sores or signs of irritation.
This is the time this file has been accessed since 07/01/97.
The University of Tennessee at Martin is not responsible for the information or views expressed here.
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