Eating Nails for Breakfast (Gennaro De Felice)

Principle(s) Investigated: Physiology, Digestive System, Nutrition, Elemental IronStandards :

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:

5.a. Students know plants and animals have levels of organization for structure and function, including cells, tissues, organs, organ systems, and the whole organism.

5.b. 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

7. 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:

a. Develop a hypothesis.

b. Select and use appropriate tools and technology (including calculators, computers, balances, spring scales, microscopes, and binoculars) to perform tests, collect data, and display data.

c. Construct appropriate graphs from data and develop qualitative statements about the relationships between variables.

d. Communicate the steps and results from an investigation in written reports and oral presentations.

e. Recognize whether evidence is consistent with a proposed explanation.

g. Interpret events by sequence and time from natural phenomena (e.g., the relative ages of rocks and intrusions).

h. Identify changes in natural phenomena over time without manipulating the phenomena

Materials:

• Magnet
• Iron-fortified Cereal
• Ziplock bags
• paper plates
• Water

All of these items can be found at your local grocery store, with exception of good magnets. I was able to find these strong magnets at Home Depot for about $2.00 dollars a pair. It is also imported to have cereal that contains lots of iron. Total is probably the best cereal for this experiment, but it would also be good to use other cereals with iron to get a contrast of how much iron is in a cup of another cereal and match it against the nutritional facts.

Procedure:

1. Have students get into small groups of 3-4.
2. Each group should have a plate, a cup of Total cereal, water, and a magnet
3. Pour the the Total cereal onto the plate and crush it with finger tips into the smallest pieces possible.
4. The first test will check to see if you can get the magnet to move any of the small pieces of total.
5. Pour the Total into the ziplock bag and pour water into the same bag.Make sure the bag is tightly sealed. Give about 15-20 minutes for the Total to dissolve int he water. Water that is more warm works quicker.
6. Place the magnet on the palm side of your hand and place the ziplock bag with the disolved Total over the center of the magnet. Rock the bag in a circular motion for a short while.
7. Turn the bag over and lift one side of the magnet to see if any black particles are stuck to the top of the bag and magnet. If so, this is Iron!
8. If time permits, hold the magnet to the plastic bag so the iron stays and drain the contents of the bag. This will allow the easy removal of the iron from the bag.

Student prior knowledge:

In order to understand this activity, students need to understand that nutrition, the digestive system, and physiology all go hand in hand together. At many stages in a child's academics, they will come across organ systems. In 7th grade life science, students will learn the basics of how the digestive system works and contains enzymes to break down the food we eat into small molecules, which are absorbed by the small intestines and enter your blood where they are transported to different parts of your body.

Explanation:

There are many breakfast cereals that contain iron (Fe) as a mineral supplement. Total cereal is the only major brand that claims to contain 100% of your recommended daily allowance of iron. As much as other vitamins and minerals we eat, metallic iron is digested in the stomach and absorbed in the small intestine. Iron is essential to human life in many ways. This experiment is designed to take the metallic iron out of the Total cereal and bring it together into a small pellet for us to actually see and realize that iron is a metal we can eat in small amounts. The secondary function of this experiment is to make analogues the process of stripping the iron from the Total cereal to the digestive system. The crunching of the cereal initially is our teeth grinding the food down into small pieces. The water that dissolves the cereal is like our stomach acid breaking down the food.

"Males of average height have about 4 grams of iron in their body, females about 3.5 grams; children will usually have 3 grams or less. These 3-4 grams are distributed throughout the body in hemoglobin, tissues, muscles, bone marrow, blood proteins, enzymes, ferritin, hemosiderin, and transport in plasma."

Source: http://www.irondisorders.org/how-much-iron-is-in-the-body

Questions & Answers:

1. Is the iron in the cereal the same iron used in nails?
   • Yes, the iron in cereal is fortified in the form of "raw" elemental iron, along with iron in compounds. However, iron in elemental form has a strong magnetic attraction while iron in compounds is not.
2. Why do we need to have iron in our body?
   • Most of the iron in humans is found in hemoglobin, which is the oxygen-transport metalloprotein in the red blood cells. Our bodies only need about 1 to 1.5 milligrams of iron per day to replace what is lost through normal daily losses such as urination, sweat, bowel movements, and tears.
3. Why doesn't the iron travel through the intestinal tracts like a coin?
   • Iron dissolves in the stomach acid because they are very small particles that break apart quickly. A penny simple does not stay in the stomach long enough to dissolve.

Applications to Everyday Life:

1. This experiment is analogous to the digestive system. The breaking apart the Total cereal into very small pieces is like your mouth beginning the process of digestion by chewing the cereal into mush. When the water is added to the bag it is acting as a solvent to break apart further the cereal and dissolve it into a liquid. This simulates the acid in your stomach breaking apart the food molecules that were swallowed.
2. Iron is necessary for hemoglobin. It's the compound in red blood cells that carry oxygen from your lungs so it can be moved throughout your body. The iron in hemoglobin gives blood its red appearance Without iron in your bloodstream, a person can experience more illnesses, fatigue, and increased heart rate and respiratory rates. The cereals we buy in store, especially Total, are packed with iron to give those who may not receive it through other food consumption a way of supplementing their dietary needs.
3. Homeostasis - This is defined as the tendency toward a relatively stable equilibrium between interdependent elements, especially. as maintained by physiological processes. Homeostasis is not dependent on iron, but it is a necessary component of the equilibrium our body needs.

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