It's Cereal Time (Christina Dempsey)
What's In Our Cereal?
Principle(s) Investigated: Nutrition, Digestive System, Physiology
Standards : Past in the appropriate California content standards.
7th: Structure and Function of Living Systems
The anatomy and physiology of plants and animals illustrate the complementary nature of structure and function. As a basis for understanding this concept:
5a. Students know plants and animals have levels of organization for structure and function, including cells, tissues, organs, organ systems, and the whole organism.
5b. Students know organ systems function because of the contributions of individual organs, tissues, and cells. The failure of any part can affect the entire system
Investigation and Experimentation
Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will:
7a. Develop a hypothesis.
7b. Select and use appropriate tools and technology (including calculators, computers, balances, spring scales, microscopes, and binoculars) to perform tests, collect data, and display data.
7d. Communicate the steps and results from an investigation in written reports and oral presentations.
7e. Recognize whether evidence is consistent with a proposed explanation
9th – 12th: Physiology
As a result of the coordinated structures and functions of organ systems, the internal environment of the human body remains relatively stable (homeostatic) despite changes in the outside environment. As a basis for understanding this concept:
9a. Students know how the complementary activity of major body systems provides cells with oxygen and nutrients and removes toxic waste products such as carbon dioxide.
Materials: Include a list of materials and sources from which they may be obtained.
Cereal
Plastic sandwich bag
Magnets
Ziploc bag
Paper towel or napkins
Water
Procedure:
Ahead of time, pour a small handful of each type of cereal into its own individual plastic sandwich bag. This way each group of students can have one bag of each cereal type (a total of two bags). Label the bags to distinguish the two easily.
1. Have students get into groups of 2 or 3.
2. Each group should have one magnet, a paper towel or napkin, and one sandwich bag of each type of cereal, two Ziploc bags, and two cups of water.
3. Have one of the students in each group smash or grind one of the bags of cereal, while another student does the same for the second bag.
4. Make sure that they grind it until the cereal is in tiny little pieces.
5. Have the students transfer the tiny bits of cereal into the Ziploc bags.
6. Add about a cup of water into each bag of Ziploc bag.
7. Let the cereal dissolve for about a minute.
8. Have another student take the two magnets and place one Ziploc bag over each magnet.
9. Have the students shake the bag slightly to make sure that the magnet has come in contact with the majority of the “slurry”.
10. Have the students slowly drag the magnet to see the iron on the other side of the bag.
11. Have the students compare the amount of iron found in each bag.
12. Have the students answer the following questions:
a. Did you see something stuck to the magnet for both magnets?
i. If yes, which ones?
b. What do you think it might be?
c. How much did you see on each magnet? Little specks, clumps, or nothing
d. Which one had the most?
e. Why do you think that might be?
13. Then talk to the students about the importance of iron and why it is sometimes added into our food.
a. What does iron do in our bodies? What is its importance?
Student prior knowledge:
The idea that nutrition, physiology, and the digestive system work hand-in-hand. In 7th grade, they briefly go over the organ systems and how we break down food to absorb nutrients/minerals, which enters the cells to be transported all over the body. In high school, they go over the importance of oxygen and hemoglobin and the specifics of the organ systems.
Explanation:
Iron is essential to our body and must be acquired from our diets. Iron is used for human growth, maintenance and cellular division. The majority of iron that is acquired comes from meat. Beef, pork, and poultry are a great source of iron. Often times, some types of food are enriched with iron to make sure people get an adequate supply of iron. In this case, we will be looking at cereal. Below is a chart of how much iron can be found in different types of cereal. Although not mentioned, Totals is the only major brand that is said to contain the daily-recommended dosage of iron.
http://apjcn.nhri.org.tw/server../info/books-phds/books/foodfacts/html/data/data5e.html
For this experiment, we will be looking at how much iron is put into our cereal. Try to choose Totals and a couple of the popular brands to show students a comparison among the brands. The students will see and realize that iron is a metal that is added to our food and that it is fine to eat it in small amounts.
Questions & Answers: Give three thought-provoking questions and provide detailed answers.
Applications to Everyday Life: Explain (don't just list) three instances where this principle can be used to explain other phenomenon.
1. What type of iron is found in cereal?
The form of iron that is added in cereal is the elemental iron (Fes), which is the completely reduced form of iron. Our body more readily absorbs reduced forms of iron (such as Fe2+) than the oxidized form (Fe3+). The same type of iron found in nails.
2. Why is iron important for us?
We need iron for oxygen transport and electron transfer in respirations. Most of the iron found in a human’s body is found in hemoglobin’s. Hemoglobins are proteins that transport oxygen in red blood cells. Every day, humans lose about less than 2 milligrams of iron per day through urination, sweat and other daily things.
3. What do you think would happen if the body did not receive an adequate supply of iron?
If there is not a sufficient supply of iron, the red blood cells in the body are not as effective at transporting oxygen. People do suffer from iron deficiency.
4. What are some other types of food that is enriched with iron?
Besides cereal, noodles and rice are enriched with iron.
Photographs: Include a photograph of you or students performing the experiment/demonstration, and a close-up, easy to interpret photograph of the activity --these can be included later.
Videos: Include links to videos posted on the web that relate to your activity. These can be videos you have made or ones others have made.
- Read labels on boxes to see the iron content.
Students can keep track of how much iron they intake everyday. They can make sure, for themselves, to keep a well-balanced diet. Also, the students will be aware of how much iron and other minerals and vitamins are present in the food they eat. Total is the only type of cereal that has 100% daily-recommended iron intake (as shown below).
Cap'n Crunch Peanut Butter Nutrition Facts
Total Nutrition Facts
- Discuss the importance of iron in the diet.
Iron is found all around us. It is found in our food, nails for construction, and many other things. Students will learn how iron does affect us when we have an excess amount or an inadequate amount. When people faint, it is due to the lack of oxygen from loss in blood pressure. But if students have experienced fainting, they can see the harm in the lack of oxygen.
- The use of cast iron pans.
Many people use cast iron pans for cooking. Most of the time, people use the iron pans for cooking meat. One reason for it being made out of cast iron is to ensure that people get a small amount of iron added into their food during every use.