Introduction: (Initial Observation)
We eat many different foods every day. Meat, bread, rice, beans, and vegetables are some of the foods that we eat. The question is why do we need so many different foods? Can we just eat rice, meat, or any thing else that we like? Is it just for taste or there are some other reasons? Some animals don’t have such a variety of foods! For example, sheep eat grass, and birds eat seeds. Can we do the same and eat one type of food every day?
In this project you will research on what foods people eat, what are in these foods, and how to make the best food choices. You will perform some experiments and finally prepare a very nice and educational display with lots of drawings and food samples
Note: For lower grades, this project is mostly a display project and does not require experiment. Ask your teacher how far you can go in your research based on your age and grade.
Find out about different foods and how they can help our body and our health. Read books and magazines or ask professionals who might know in order to learn about the effect of different foods in our body. Keep track of where you got your information from.
Your initial study will focus on the research performed by others in this subject. The internet is a good place to start. US Department of agriculture has good website for kids. There you can find lots of valuable information in addition to a beautiful drawing known as food pyramid. A food pyramid is a graphical presentation that shows what types of foods are more important for our health. As a part of your presentation, you can draw the food pyramid on a large board and place it on the center of your display. You may also want to gather some real food items, (small) and include it in your display or hang them in a proper place in your food pyramid. This is a sample of food pyramid.
A nutrition pyramid, however, can be very educational and easy to understand. Different sections of nutrition pyramids represent different types of food. These sections are described here.
Fats, Oils, & Sweets (Use Sparingly)
- Go easy on fats and sugars added to foods in cooking or at the table–butter, margarine, gravy, salad dressing, sugar, and jelly.
- Choose fewer foods that are high in sugars–candy, sweet desserts, and soft drinks.
- The most effective way to moderate the amount of fat and added sugars in your diet is to cut down on “extras” (foods in this group). Also choose lower fat and lower sugar foods from the other five food groups often.
Milk, Yogurt, & Cheese (2-3 Servings)
- Choose skim milk and non-fat yogurt often. They are lowest in fat.
- 1 1/2 to 2 ounces of cheese and 8 ounces of yogurt count as a serving from this group because they supply the same amount of calcium as 1 cup of milk.
- Choose “part skim” or low fat cheeses when available and lower fat milk desserts, like ice milk or frozen yogurt. Read labels.
Meat, Poultry, Fish (2-3 Servings)
- Choose lean meat, poultry without skin, fish, and dry beans and peas often. they are the choices lowest in fat.
- Prepare meats in low fat ways:
- Trim away all the fat you can see.
- Remove skin from poultry.
- Broil, roast, or boil these foods instead of frying them.
- Nuts and seeds are high in fat, so eat them in moderation.
Vegetable Group (3-5 Servings)
- Different types of vegetables provide different nutrients.
Eat a variety of vegetables.
- Include dark-green leafy vegetables and legumes several times a week–they are especially good sources of vitamins and minerals. Legumes also provide protein and can be used in place of meat.
- Go easy on the fat you add to vegetables at the table or during cooking. Added spreads or toppings, such as butter, mayonnaise, and salad dressing, count as fat.
Fruit Group (2-4 Servings)
- Choose fresh fruits, fruit juices, frozen fruit, canned fruit, or dried fruit. Go easy on fruits canned or frozen in heavy syrups and sweetened fruit juices.
- Eat whole fruits often–they are higher in fiber than fruit juices.
- Count only 100 percent fruit juice as fruit. Punches and most fruit “drinks” contain only a little juice and lots of added sugars.
Bread, Cereal, Rice, & Pasta Group (6-11 Servings)
- To get the fiber you need, choose several servings a day of foods made from whole grains.
- Choose most often foods that are made with little fat or sugars, like bread, English muffins, rice, and pasta.
- Go easy on the fat and sugars you add as spreads, seasonings, or toppings.
- When preparing pasta, stuffing, and sauce from packaged mixes, use only half the butter or margarine suggested; if milk or cream is called for, use low fat milk.
What Counts as One Serving?
The amount of food that counts as one serving is listed below. If you eat a larger portion, count it as more than 1 serving. For example, a dinner portion of spaghetti would count as 2 or 3 servings of pasta.
Be sure to eat at least the lowest number of servings from the five major food groups listed below. You need them for the vitamins, minerals, carbohydrates, and protein they provide. Just try to pick the lowest fat choices from the food groups. No specific serving size is given for the fats, oils, and sweets group because the message is USE SPARINGLY.
|1 cup of milk or yogurt||1 1/2 ounces of natural cheese||2 ounces of processed cheese|
|2-3 ounces of cooked lean meat, poultry, or fish||1/2 cup of cooked dry beans, 1 egg, or 2 tablespoons of peanut butter count as 1 ounce of lean meat|
|1 cup of raw leafy vegetables||1/2 cup of other vegetables, cooked or chopped raw||3/4 cup of vegetable juice|
|1 medium apple, banana, orange||1/2 cup of chopped, cooked, or canned fruit||3/4 cup of fruit juice|
|1 slice of bread||1 ounce of ready-to-eat cereal||1/2 cup of cooked cereal, rice, or pasta|
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
The purpose of this project is to find out what types of food gives us enough energy and keeps us healthy.
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.
Food related variables that may affect our health, growth, and energy are the types and the amounts of foods that we eat. For this study we select the variables as follows:
Independent variable (also known as manipulated variable) is the type of food.
Dependent variable (also known as responding variable) is the weight.
Constants are the type and initial age of animals you test.
Controlled variables are other environmental conditions such as light and temperature. (You make sure that all test animals are growing under the same light and temperature conditions)
I hypothesize that sweet foods gives us energy and anything that our body likes is good for our health and growth.
Note: You can have any other hypothesis that you like. Your experiment will prove or disprove your hypothesis. If you change your question/purpose or your hypothesis, you may need to do some changes in your experiments as well to match them.
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”
Introduction: In this experiment, we will feed a few pet mice with different types of foods and measure their growth. Use 4 young, same size pet mice and keep them in 4 identical cages. If you are going to custom build the cages yourself, remember the pet mice need enough light and oxygen. They can chew plastic and they can climb and jump in order to get out of the cage.
We will feed the first mouse with food and sugar water. The second mouse with food and milk and the third mouse with both (so he can choose). The fourth mouse will be the control, so we feed him with food and water. We will then monitor the weight and the length of each mouse and record it. For this experiment you can almost use any of various small, mouse like rodents such as a gerbil, a rat, and a guinea pig. The white rat in the picture is an albino rat. Albino rats are very good for such experiments because they will eat any food we eat. They also grow quickly and have a similar digestive system to us.
Clean your pet mice cages often. Be sure you put new food, water, milk, and sugar water into the cages.
In order to clean the cage, take the mouse out of the cage and hold him in a temporary and safe place. Dump the old bedding out of the cage into the garbage. Rip new pieces of paper towels for the bedding and lay down the new fresh bedding. Put new food and sugar water back into the cage. Then let the mouse back in the cage.
We feed the mice two fruits, two vegetables, oatmeal and meat in addition to their specific drink (water, sugar water, milk). You should always try to feed the mice at the same time of the day.
The experiment mouse drinks sugar water, milk, or both and the control mouse drinks water. Monitor the mice growth for about 4 weeks.
Take each mouse out of the cage and weigh them in the beginning of the experiment and once a week after that. You may need to put the mouse in a smaller plastic container for weighing. At the same day that you weigh the mice, also measure their total length (head to tail) and their tail length.
Have someone hold the mouse while you measure the length. Make sure you hold the mouse secure because it is likely to squirm.
Use a ruler to measure the length. Measure the length in centimeters.
Weigh and measure the length of the mice once a week . Try to measure them on the same day of the week.
Record the results of your experiment in a table like this:
|Weight/ Length||Mouse 1||Mouse 2||Mouse 3||Mouse 4|
|First day||6 grams /10 cm|
|After 7 days|
|After 14 days|
|After 21 days|
|After 28 days|
After the fourth week we trade drinks. What do you think happens?
If you want to see the effect of drinks mush faster, reduce the amount of food or limit the food to one type only (only vegetables or only oatmeal).
With mice, you can do a variety of different tests to see how the food affects their health, energy (activity), and growth (weight and length).
Materials and Equipment:
List of materials can be extracted from the experiment design section.
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
Not much calculation is needed.
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.