GRADE: Fourth

CONTENT STANDARD: Life Science

CONTENT TOPIC: Anatomy

CONCEPT: The human body is composed of sensory organs which detect heat, light, and sound.

CONTENT OBJECTIVE: 4G1.00 To understand the sensory organs and their function

INSTRUCTIONAL OBJECTIVES: The learner will:

1.01 name the major parts of the ear and explain the function of each.
1.02 name the major parts of the eye and explain the function of each.
1.03 name the major parts of the skin and explain the function of each.
1.04 name the major parts of the nose and explain the function of each.
1.05 name the major parts of the tongue and explain the function of each.

I. Ear
A. Outer
B. Middle (anvil, stirrup, eardrum, hammer)
C. Inner (cochlea, semicircular canals)
D. Auditory Nerve
II. Eye
A. Iris
B. Pupil
C. Lens
D. Retina
E. Cornea
F. Optic Nerve
G. Vitreous Humor
H. White of the Eyeball
III. Skin
A. Epidermis
B. Dermis
C. Fat Cells
D. Pores
E. Sweat Glands
F. Oil Glands
G. Nerve Fibers
H. Melanin
IV. Nose
A. Nasal cavity
B. Tiny Hairs
C. Special Cell Lining
D. Nerve Cells
V. Tongue
A. Taste Buds
B. Olfactory Nerves

TN COMPONENT OF SCIENCE: Process Of Science

TN GOAL:

To enable students to demonstrate the process of science by posing questions and investigating phenomena through language, methods and instruments of science

1.1 OBSERVING - The senses are used to develop an awareness of an event or object and the properties thereof.

1.1a Observing is a process used to develop an awareness of the surrounding environment.

BENCHMARK: Awareness of our surroundings is a result of individual observations and prior knowledge.

TIME REQUIRED:

Five instructional periods

Ear, eye models; pictures of charts detailing the parts of the ear, eye, skin, nose, and tongue. Ask a local optometrist for an eye chart, diagram of eye; teacher-made ditto (see active participation)

This Classroom Connector addresses Instructional Objective 1.01.

SET:

Raise your hand if you can hear what I'm saying. (response) Raise your hand if you can show us how to walk a straight line. (response - Call on someone.) The ability to hear and the balance required to walk a straight line is in the ear. The Amazing Ear is what we will discuss today.

The ear is divided into three main areas. These are the outer, middle and inner ear. Where do you think the outer ear is? (response) Of course it is the ear flap on the outside of our heads plus the ear canal. The ear flap collects sounds and sends them down the ear canal to the middle ear. We have learned, in other lessons, that sound vibrates. These vibrations in the middle ear are passed on to the eardrum in the inner ear. It is the inner ear that helps control balance.

(Explain to students the difference between hearing and listening. Have students listen for 3-5 minutes and then record all the sounds they heard. This activity could be conducted in the classroom or the playground.)

Take out a sheet of paper and write the two things the ear does. (Hearing, Balance) Now list the three parts of the ear. (pause, seek responses, then summarize)

This Classroom Connector addresses Instructional Objective 1.02.

SET:

I'm going to write some words on the board. When you recognize where these words belong or what they are referring to, raise your hand. (Write vitreous humor, pupil, cornea, retina, etc. and pause for a moment between each word. Continue until someone guesses the word.) All of these words name a part of the eye. Today we will talk about the function of each of these parts.

(Have diagram of eye displayed for students to see.) Our eyes are wonderful organs. They are a very important part of our daily lives, for without them, the whole way we live would be changed. Some of you may have relatives or friends who have poor vision and you've seen how they had to adjust their lives because of this. The eye is very complex and very sensitive. On a clear night, a person on a mountain can see a match being lighted as far as 80 kilometers away.

There are eight parts of the eye that we will talk about today. The EYELID is for protection of the eye. What is the first thing you do when you notice something coming very fast to your eye? (You blink.) Yes, blinking is almost a reflex. Without thinking, we blink to protect our eyes. The eyelid also spreads the tears to wash out diseases. Our eyes are covered by a tough outer layer. The front of this layer is called the CORNEA. The cornea is curved over the dark opening of the eye ball and bends incoming light rays. The PUPIL is the black part of the eye. The pupil changes size according to the amount of light we're in. If there is a strong light, the pupil gets smaller. If there is a weak light, the pupil gets larger. The muscles that change the size of the pupil are located in the IRIS. The iris is the colored area of the eye.

The LENS is the eye's primary light focus. It is located behind the pupil. Muscles attached to the lens allow it to focus light.

The two remaining parts of the eye are the VITREOUS HUMOR and the WHITE OF THE EYEBALL. The vitreous humor is the clear jelly that protects the retina. The white of the eyeball holds all the parts together in the socket.

(The following activities are suggested:

1. Have students draw and label parts of the eye as shown on the diagram.

2. Teacher-made or any available word search ditto using words listed in outline.)

On a sheet of paper, write two of the parts of the eye we have discussed today and explain their functions. (pause, seek responses, then summarize)

This Classroom Connector addresses Instructional Objective 1.03.

SET:

We have talked about the ear and the eye. Today, we'll talk about a sensory organ that is the largest organ in your body. If you touch your cheek or your arm, you are touching this organ. We will be discussing your skin.

Your skin is an organ because it is made of different tissues that work together to do a special job. Your skin weighs about two kilograms while an adult's skin can weigh as much as three kilograms. Your skin has nerves that, when you touch something, send messages to the brain that tell you whether something is hot, cold, smooth, sharp, rough, etc.

Your skin covers your body protecting your blood vessels, nerves, and muscles from dirt and germs. The tiny blood vessels in your skin control body temperature by expanding and contracting as needed.

Skin is made of two layers of specialized cells called the epidermis which is the outer layer and the dermis which is the inner layer. The epidermis has an inner and outer layer of cells. The inner layer is made up of living cells that are always making new cells. These new cells push the older cells upward until they die. This layer of dead cells makes up the outer layer. These dead cells are always being rubbed off in bathing and wearing clothes. The dermis lies under the epidermis. These cells sometimes mix, causing the layers to stay joined together. The dermis has elastic fibers that make it possible for your skin to stretch. The dermis contains blood vessels that carry food and oxygen to the cells in the skin. Oil glands are found in the dermis. They secrete a substance that helps keep the skin soft.

Fat cells are found below the dermis. These fat cells help keep your body warm. They soften any blows your body receives.

Pores are tiny openings on the surface of the skin. Sweat glands are small coiled tubes in the dermis that carry sweat to the surface of your skin through pores helping to cool your body when it is hot.

Melanin is a substance in the skin cells that controls hair and skin color. The amount of melanin in your body is hereditary. Those with darker skin have more melanin. Freckles are small spots of melanin.

Place different objects in a bag. Ask students to feel the objects without looking at them. Explain that skin can help students "see" through touching.

Finish these sentences:

1. The largest sensory organ of the body is the ________. (skin)

2. The two layers of skin are the ________ and the ________. (dermis, epidermis)

3. ________ secrete a substance that helps keep the skin soft. (Oil glands)

4. ________ cells help keep your body warm and soften any blows to your body. (Fat)

5. Tiny openings on the skin surface are ________. (pores)

6. Small, coiled tubes in the dermis are ________ glands. (sweat)

7. A substance that controls hair and skin color is ________. (melanin)

Draw a cross-section of the skin, labeling the dermis, epidermis, oil glands, fat cells, pores, sweat glands, and melanin.

This Classroom Connector addresses Instructional Objective 1.04.

SET:

One of our sensory organs is right up front and center of our faces. It is the nose. We will be finding out what parts make up the nose and what the function of each part is.

The nose is part of the respiratory system. You breathe in air through the nose. The nasal cavity is an air passage that is located behind the nose. It is divided into two parts, a right and left passageway. Heat from the blood vessels in the nasal cavity warms the air as you breathe. Special cells in the nasal cavity wall add moisture to the air you breathe. Because of these blood vessels and special cells, air you inhale is warmed and moistened before it reaches your lungs. There are many tiny hairs inside your nose that trap small specks of dirt. This cleans the air you breathe. Special cells line the inside of the nose. They protect you by warning you if something harmful is in the air, something like smoke or spoiled food. Nerve cells in your nose make you sneeze in a dust-filled room thereby keeping dust from getting deeper inside your body.

Have an assortment of "scents" in separate plastic bags. (Suggestions - lemon, onion, cigarette ashes, ketchup, cinnamon Blindfold students and let them try to guess what the substances are.)

The nose does what three things to the air that is inhaled? (Cleans, Warms, Moistens)

This Classroom Connector addresses Instructional Objective 1.05.

SET:

If your nose were a little stuffy, your eyes were closed, and you were not allowed to touch anything with your hands, is there any way you could recognize a lemon? (response) Yes of course, you could taste it! We will find out today that the tongue is a sense organ with taste buds and it works with the nose (Sense of smell).

You taste with your tongue. Your tongue has special taste buds that can register sweet, sour, salty, and bitter. The taste buds are nerve endings in the tongue. The taste of sweet is registered on the tip of the tongue, salt taste buds are located on the sides toward the front, sour is on the sides toward the back, and bitter is registered in the center back.

Although you can tell just with your sense of taste that a fruit is sweet, most flavors are recognizable using the sense of taste in conjunction with the sense of smell. Connections to the olfactory nerve are located in the upper passage of the nasal cavity. The olfactory nerve is used for smell.

(With a partner) One partner will hold nose and close eyes. The other partner will put a slice of either apple or pear in that person's mouth. Is it possible to tell the apple from the pear without smelling? (Probably not) Let go of your nose to see if it is easier to tell the difference. Swap to allow your partner to try.

Help me complete these statements:

1. Your taste organ is your ________.(Tongue)

2. It has special taste that can register ________, ________, ________, and ________. (Buds, sweet, sour, salty, bitter)

3. Also helping your tongue to taste is your ________. (Nose)

4. The connects the nasal cavity to the brain __________ ________. (Olfactory nerve)

Label a teacher-made ditto of the tongue showing the areas for sweet, sour, salt, and bitter taste buds.

This is the time this file has been accessed since 07/01/97.

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