Objective The aim of this lesson is to introduce students to the role of contrast materials in medical imaging. It will help students to understand how contrast materials aid in making internal organs and their functions more visible.
Materials Needed Milk bottles, food coloring, eye droppers, water.
Procedure
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1. Have students place an empty milk bottle on the opposite end of the room.
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2. Have students fill a second milk bottle with clear water next to the bottle.
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3. Have students observe from the opposite side of the room while one student uses a dropper to add a dark colored food coloring to the bottle with water.
Observations and Analysis
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1. Students will be able to see the outline of the empty bottle.
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2. As the coloring is added, the students will find the bottle is given more definition.
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3. The bottle with the colored water will allow the students to see the outline of the bottle more clearly.
Vocabulary
1. Contrast
2. Medical Imaging
3. Internal Organs
Lesson Plan III: Can Light Rays Bend Through Solid Materials
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Objective The concept of projecting an image on another surface is abstract to many students.
This lesson is designed to show that light rays do not have the ability to bend. It will help students to understand why x-ray machines aim radiation directly at the object as opposed to attempting to curve the rays.
Procedure
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1. Set up a flashlight at one end of a piece of rubber garden hose about 90 cm. Long. Curve the hose. Explain the light rays are being emitted from the flashlight. Ask students if they are able to see the light through the opposite end of the hose.
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2. Straighten the tube by fastening it to a measuring stick with rubber bands. Have another student shine the light into it. Ask students to explain what they see.
Observations and Analysis When light travels through a substance, it usually travels in straight lines. Light usually does not bend, it does not turn corners.
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1. When the garden hose is curved, the student will not be able to see the light rays being emitted from the other end.
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2. When the garden hose is straight, the student will be able to see direct light coming from the opposite end.
Vocabulary
1. Cm.—centimeter
2. Bend
3. Substance
Materials Needed Flashlight, rubber garden hose approximately 90 cm. Long, measuring stick, rubber bands.
Lesson Plan IV: Magic Camera
Objective Many middle school students have not had the opportunity to take a photography class and have difficulty perceiving how one can get an image of an actual object on a plane different from that object.
This lesson will help students understand how one is able to project an image of an object. This will make the concept of medical imaging more concrete.
Materials Needed Cereal box or tin can, wax paper or tracing paper, rubber bands, needle.
Procedure
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1. Remove end of a box or tin can.
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2. Cover the open end with wax paper or tracing paper.
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3. Secure the paper with a rubber band.
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4. Prick a hole in the center of the opposite end of the can with a needle.
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5. Slightly elevate the can on a small hard covered book.
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6. Place a lighted candle about four decimeters from the can.
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7. Place the side with wax paper toward you and the other end toward the candle.
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8. Observe the image on the wax paper end.
Observations and Analysis Unlike sound, light has the ability to travel in a vacuum. Light usually travels in straight lines. Although this is not like a regular camera, it does form an image.
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1. The image is made because the rays of light travel in straight lines.
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2. As this “magic camera” is moved back and forth, the size of the image changes.
