YOU ARE WHAT YOU EAT- NUTRITION

MASTER TEACHER: Andrea Cantu

Grade Level: 6-8

Time allotment: Three 45-minute class periods.

Overview: Food is a necessary component to living systems. Food replaces energy that is used, and provides the fuel for growth. For proper maintenance of a living being, a variety of food groups should be eaten. The digestive system begins digestion with a mechanical breakdown and then a chemical breakdown. Nutrients are removed from the small intestine and undigested materials are processed and released through the large intestine.

Through the activities presented in this lesson, students will become familiar with human needs relating to nutrition (food groups) and the digestive process. Students will first sort food into the basic food groups and then later regroup into carbohydrates, proteins, and fats. Students will simulate peristalsis. Students will search a pre-selected web site to reinforce concepts presented in the video and to acquire further information on the subject. Experiments will be conducted to test for starch (carbohydrates), fat, and vitamin C.

Subject Matter: Science and Technology

Learning Objectives:

Students will be able to

List selected food items into nutritional groups
Define the words ingestion and digestion
Describe the functions of the 10 major organs of the digestive system
Demonstrate peristalsis
Gather further information on the digestive system via the internet
Students will test for starch, fat, and vitamin C

Standards

From the National Science Education Standards, grades 5-8

1) The human organism has a system for digestion. (NSES C)

2) Food provides energy and nutrients for growth and development. Nutrition requirements vary with body weight, age, sex, activity, and body functioning. (NSES F)

Media Components

Video
Our Human Body From Science Source: #110 Nutrition

Web Sites

The Digestive System
http://www.msms.doe.k12.ms.us/biology/anatomy/digestive/digestive.html
This site describes the 10 main organs of the digestive system.

The Food Factory
http://www.imcpl.lib.in.us/nov_dig.htm
This site has a labeled diagram and four facts about the digestive system.

Food Pyramid Guide
http://www.ganesa.com/food/index.html
This site deals with food groups and gives a brief discussion on each group.

Scurvy
http://kids.infoplease.lycos.com/ce6/sci/A0844162.html
This site is part of the kids’ almanac of infoplease.com. This entry is the information provided by the online encyclopedia about scurvy.

Materials

For the class

Ping-Pong ball

For each group of four students:

Set of food cards
Cracker
Iodine
Dropper
Butter (regular and low fat)
Brown paper bag or brown paper towel
Lemon juice
Indophenol (blue in color)

For each student:

Nutrition worksheet packet
Pen or pencil

Prep for Teachers

Prior to the teaching, bookmark all of the Web sites used in the lesson. Cue the videotape to the appropriate starting point. Prepare the handouts for each student. Prepare food cards for the group activity. Organize lab supplies.

Introductory Activity:

The following activity will prepare your students for the concepts of the basic food groups. Later the food cards will be sorted in different nutritional groupings, such as carbohydrates, fats, and protein.

Step 1: Preparation of the food cards

Glue five to six food pages containing the 25 food words onto a 8 ½” x 11” piece of poster board. Laminate the finished product and cut out into rectangles. For a simpler method copy the five to six food pages on different colored paper and cut out.

Step 2: Conduct the activity

Give each group a set of food cards. Ask the groups to organize their cards into categories. Students must explain their reasoning for their food card groupings.

Step 3: Analysis of the activity

Say, “Explain how you grouped your cards. (accept all reasonable answers) What are the four major food groups? (Dairy products, meats and nuts, grains and cereals, fruits and vegetables)

Learning Activities

Step 1: Focus for media interaction

To provide your students with a FOCUS FOR MEDIA INTERACTION, say, “Later we will group the cards into another set of categories. Let’s watch the video on nutrition to see into what new groupings we can place these cards.”

START the video, Our Human Body From Science Source: Nutrition, where the words “Roots of Nutrition” appear on the left of the screen. A caterpillar is eating a leaf. The audio is music. PAUSE. Say, “Listen for the uses of food. Record your answer on question #1.” RESUME the tape when the audio is music and a parrotfish is swimming on the screen.

Step 2: Introduction to the Food Pyramids and Types of Consumers

FAST FORWARD the tape until the visual is a wildcat eating a rodent. The audio is “Different levels make up the food pyramid.” PAUSE the tape. Say, “What are some uses for food? (stay alive, develop, and replace energy) For questions 2-5, listen for the groups of organisms that are producers and consumers.” PLAY the tape to the section where the sound of typing is heard and the visual of the following words appear, “Which type of animal uses the food it eats most effectively?” PAUSE the tape. Say, “What is a

primary producer? (plants) Name two primary consumers. (herbivores and omnivores) Name two types of secondary consumers. (carnivores and omnivores) What animal uses its food the most effectively? (omnivore) For answers to numbers 6-8, listen for the percentage of the food that is used and discarded, and the types of substances humans need to eat. PLAY the tape until a cartoon of a human body is surrounded by icons of nutritional substances. The audio is “Each of them is obtained from eating or ingestion.” PAUSE the tape.

Step 3: Human Needs and Composition

Say, “What percentage of our ingested food is used? (10%) discarded? (90%) What food substances do humans need? (water, carbohydrates, fat, protein, minerals and vitamins) What does ingestion mean? (to eat) In this next segment questions 10-12 will be addressed. Listen for the percentage of water of which the body is composed and the substance that is a primary building block for the human body. PLAY the tape until the video shows icons of nutritional substances. The audio is “The remainder must be obtained through our diet.” PAUSE the tape. Say, “ What percentage of the human’s body weight is water? (70%) What substance is the building block for muscles? (protein) What two life stages need more protein?” (before birth & childhood)

Step 4: Nutrition

Say, “In this next clip you will listen for the composition of protein and how many amino acids the body manufactures naturally. (questions 13 and 14) For questions 15 – 18 record the foods that contain protein, fat, and carbohydrates. PLAY the tape until the screen shows people surrounding a campfire. The audio is, “In order to stay alive humans need minerals.” PAUSE the tape. Say, “ What substance make up proteins? (amino acids) How many amino acids does the body manufacture naturally? (10) What foods contain protein? (milk, cheese, meat, poultry, fruit, vegetables, and cereal. Fats? (butter, nuts, oil, meat, and cream) Carbohydrates? (potatoes, cereal, noodles, and sugar) What two substances provide the body with fuel? (carbohydrates and fats) For 19 and 21, listen for the uses of calcium and iron, and what materials the human body absorbs rapidly. Record the answer to 20 when you hear what vitamin deficiency causes scurvy. For 22, define digestion. PLAY the tape until music is heard and a visual with a split screen appears. On the left side of the screen there is a cartoon human body and on the right side is a cartoon human head. PAUSE the tape. Say, “Why does the human body need calcium? (bones) Iron? (blood) What materials does the human body absorb rapidly? (mineral salts, water, vitamins, and glucose.) Define digestion.” (food is broken down into its basic components) At this point in the lesson students may get back into their groups with the food cards. Have students reorganize their cards into food groups relating to protein, carbohydrates, and fats.

Step 6: Digestive Process

Say, “In this next segment record in #23 the length of the esophagus, small intestine, and large intestine. For #24, write down the length of time that food is stored in the stomach. Listen for #25, the amount of gastric juice that the stomach produces. PLAY the tape to the section where the sound of typing is heard and the visual of the following words appear, “How much gastric juice does the human stomach produce?” PAUSE the tape. Say, “ What is the length of the esophagus? (6 inches) Small intestine? (12 feet) Large intestine? (6 feet) How long does food stay in the stomach? (1 hour) How much gastric juice is produced in the stomach? (1 pint) Listen for the function of the small and large intestine. Record your answers on 26 and 27. Give the answer to #28 as to the number of bacteria in the body.” PLAY the tape to the section where the sound of typing is heard and the visual of the following words appear, “How many bacteria does a human body carry?” PAUSE the tape. Say, “ What is the function of the small intestine? (absorb nutrients) Large intestine? (absorb water) How many bacteria are in the human body? (billions) This next clip describes the kind of consumer a human is and what factors determines man’s diet. STOP the tape when music is playing and the screen displays the words “Instant Replay”. Say, “ What type of consumer is a human? (omnivore) Explain. (Humans can eat both plants and animals.) What factors determines a human’s diet? (climate, cultural/ religious, and fertility of the soil)

Culminating Activity

The following simulation will help students to understand the concept of peristalsis.

Say, “We have seen in the video how food moves along the digestive system. In this activity we are going to simulate the squeezing process in the intestine or esophagus. The squeezing action is called peristalsis.”

Step 1: Beginning the Peristalsis Simulation

Have a Ping-Pong ball or another small smooth surfaced object to pass through students’ hands. Have students line up in front of the classroom in an alternating pattern. The alternating pattern is one student is facing the front of the classroom while the adjacent student is facing the back of the classroom. This pattern is repeated down the line. Students will outstretch arms, keeping fists together, and their fists touch the students’ fists on either side. The person at the beginning of the line will be given an object to pass through his/her own hands as well as manipulating the object into the next person’s hand. The students must not drop the object. They can only use the squeezing action of the hands to push the object down the line.

Step 2: Wrapping up the Simulation

Say, “What is the squeezing action of the intestine or esophagus called? (peristalsis) How difficult was it to move the object through your hands? (accept all reasonable answers) It takes food eight hours for food to digest. What causes your stomach to growl? (peristalsis) Is your stomach the organ that is making the noise? Explain. (The squeezing or peristalsis in the intestine makes the growling noise.) If you school has a stethoscope have students listen to sounds of lower abdomen.

Step 3: Web Search

Bookmark the website titled “The Digestive System. Have students answer the web questions on their nutrition worksheet.

Step 4: Setting up the Labs

Each group member has a specific job. (Materials gatherer, Investigator, Reporter, Clean Up) These jobs rotate every lab. After the material gatherer has collected materials, (cracker, lemon juice, butter (both types), test tube, dropper, brown paper towel or bag, iodine, and indophenol) the investigator will conduct the experiments.

Step 5: Starch Experiment

Have investigator place a drop of iodine on the cracker. Food that contains starch will turn blue-black. Have student record their data on their worksheets.

Step 6: Fat Experiment

Have investigator rub a small amount of butter on the brown paper towel or bag. Repeat this process with the other type of butter. Fat or oil makes a spot on the paper. Light can pass through the paper at that spot. Have student record their data on their worksheets.

Step 7: Vitamin C Experiment

Have investigator fill one test tube with 15 ml of indophenol. Add a few drops of lemon juice. Shake the test tube once and then shake it again. Vitamin C makes indophenol lose its color. Have student record their data on their worksheets.

Cross-Curricular Extensions

LANGUAGE ARTS
Write a story about a journey through the digestive system.
Write a story in a digestive organ’s point of view.

ART
Make a guts T-shirt. (Draw the digestive system on the outside of a T-shirt.)

HISTORY
Have students research vitamin deficiency diseases that effected sailors a century ago.
Have students research the origin of the term “scurvy dogs”.

Community Connections

Have the school nurse talk to students about proper nutrition.
Have a local nutritionist talk about preparing well-balanced meals.

Student Materials

Each student will have one Nutrition worksheet packet.

NUTRITION WORKSHEET

1) Why do we need food? ______________, _____________, ___________

2) Primary producers are . . . . . . . . . . . . . . ___________________

3) Primary consumers are __________________ or ___________________

4) Secondary consumers are _________________ or __________________

5) Which type of animal uses the food it eats most effectively? __________

6) What percent of the food we ingest is used? . . . . . . . _____________

7) What percent of the food we ingest is discarded? . . . . _____________

8) What substances do humans need to eat? _____________, ___________, _______________, _________________, ______________________.

9) Define the word ingestion. . . . . . . . . . . _________________

10) What percentage of a human’s body weight is water? _______________

11) What substance is the building block for muscles?
and chemical reactions? . . . . . . . . . . . . . . ________________

12) What life stages need more protein? ____________ & ______________

13) Protein is made up of . . . . . . . . . . ____________________

14) The body manufactures ____ amino acids and the rest we must obtain from the food we eat.

15) What foods contain protein? ___________________________________

16) What substances provide the body with fuel? ______________________

17) What foods contain fat? ______________________________________

18) What foods contain carbohydrates? _____________________________

19) Tell what part of the body the following minerals are used.

Calcium _____________________ and Iron ____________________

20) What vitamin deficiency causes scurvy? . . . . . . . _______________.

21) What materials are absorbed rapidly by the human body? ___________, __________________, ________________, ___________________.

22) Define digestion. ____________________________________________

23) What is the length of each of the following organs.

a) esophagus ______________ c) small intestine _______________

b) large intestine ____________

24) How long does food stay in the stomach? ________________________

25) How much gastric juice does the stomach produce? ________________

26) What is the function of the small intestine? _______________________

27) What is the function of the large intestine? _______________________

28) How many bacteria does a human body carry? ____________________

29) What type of consumer is a human? . . . . . . . __________________

30) Name the three things that determine a human’s diet. ___________________, _________________, _________________.

Digestive System Web Search
Search the following site for the answers to the questions below:
http://www.msms.doe.k12.ms.us/biology/anatomy/digestive/digestive.html

1. Food substances are changed into forms that can be ________________.

2. Name the 10 major organs of the digestive system.

a. ___________________ f. ___________________

b. ___________________ g. ___________________

c. ___________________ h. ___________________

d. ___________________ i. ___________________

e. ___________________ j. ___________________

3-5. Where does digestion begin? . . . . . . . . . . . . . . . . . . . ______________ and its two functions are _________________ and _______________.

6-8. Name three functions of the stomach. ___________________________, ____________________________ and ________________________.

9. What is the function of pepsin? _________________________________

10. What is chyme? ____________________________________________

11-12. What two organs secrete substances into the small intestine? ___________________________ and _________________________

13-15. Name three functions of the large intestine. ____________________, ____________________________ and ________________________

16. Does the liver alter the composition of toxic substances?__________

17-18. Bile salts enhance the absorption properties of___________________ and _______________________ (A, D, E, K)

19-20. Name 4 substances the pancreas breaks down. __________________, _______________, __________________ and_________________.

STARCH EXPERIMENT

What substance did you use to test for starch? . . . . . . ____________
Did the cracker the turn blue-black? . . . . . . . . . . . . . ____________
Does the cracker have starch? . . . . . . . . . . . . . . . . . . _____________

FAT EXPERIMENT

Did the butter make a spot on the paper? . . . . . . . . . . . . . __________
Which type of butter made a larger spot? . . . . . . . . . . . . __________

VITAMIN C EXPERIMENT

What substance did you use to test for starch? . . . . . . ____________
Did the indophenol lose its color? . . . . . . . . . . . . . . . . . . __________
Does lemon juice have vitamin C? . . . . . . . . . . . . . . . . . . _________

SWISS CHEESE	WHITE SUGAR	BROWN SUGAR	OAT CEREAL

WHITE FLOUR	WHEAT FLOUR	CORN FLAKES	BRAN CEREAL

RICE	APPLES	ORANGES	GRAPES

LETTUCE	CARROTS	HAM	TURKEY

CHICKEN	FLOUNDER	BEEF	SALMON

AMERICAN CHEESE	CHOCOLATE MILK	WHITE MILK	BUTTER

Updated: April 01, 2008