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TRANSCRIPT
Grace UwaseJanuary 2016
High-speed Energy
Description: The activity uses group and individual experiments to detect sugar and protein
content in different drinks, while students discover nutritional sources of energy.
Student will test:
1. Whether different drinks will produce the same amount of gas to inflate a balloon/glove
2. The amount of sugar in different drinks
3. The drinks for protein content.
Student will observe and understand:
1. That there are different kinds of sugars, and the body uses them differently
2. That the amount of gas produced correlates with the amount of sugar used for energy.
3. There are different sources of nutrients, but the body does not use them all the same way.
Recommended: 2nd to 8th grade
Time required:
Class: 40-60 minutes, prep: 10 minutes
Key concepts
Energy: Commonly found in the forms of light, heat and electricity, energy is the power
needed to do work. Biologically, all organisms require energy to carry out any function.
Macromolecules: Large molecules made up of smaller subunits. The most important
biological macromolecules are carbohydrates, proteins, and lipids
Carbohydrates: Also known as sugars, carbohydrates are used to provide and store
energy. They can be classified as monossacharides, oligosaccharides, and
polysaccharides.
Proteins: These are the most diverse macromolecules. They are involved in catalysis of
biological reaction, supporting living organisms, making up membrane channels and
receptors, etc.
Lipids: These macromolecules are used to provide insulation and act as a concentrated
source of energy, and they are insoluble in water
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Grace UwaseJanuary 2016
Background story:
Your friend Jamie came over to your house, and you took her to the new soccer field to
play with your other friends. But she did not tell you that she did not have breakfast before
coming over, and you know that she often faints when her energy levels go down. You decide to
take her home so that your mom can give her something to keep her energy high, but no one is
home when you get there. Luckily, you are part of the League of Little Scientists. You can
determine which drink to give her so that her energy levels stay high when you go back to finish
the soccer game.
Materials: o Orange juice o Milk o Orange Kool-Aid solutiono Gatoradeo Gloveso 335 ml Coca-Cola bottleso Hot plateo Yeast
o Hydrometerso 400 mL beaker or largero Spot plateo 1 ml plastic pipets o Biuret reagent (can purchase or
make)
Prep time:
*This experiment has three main components: (1) fermentation experiment, (2) sugar test using
hydrometers, and (3) protein test. 1 is best done as a class to prevent using lots of resources and
can easily allow the class to test a variety of drinks at the same time. 2 and 3 are best done
individually or as small groups.
1) For part 1, for each drink you will need a Coca-Cola bottle, a beaker for heating, and a
glove. This part will also need hot plate(s), measuring teaspoons, and funnels
2) For part 2 and 3, each team will need a hydrometer, a spot plate, and pipettes for
measurement
3) Prepare Kool-Aid solution by adding a whole packet in 500 ml of water.
4) To prepare Biuret reagent: you will use 6M NaOH and 20% copper II sulfate. To make
20% copper II sulfate, measure 0.2 g of CuSO4 and dilute to 100 mL. If it is easier to
purchase a Biuret kit instead, look under “special notes and costs” for more information.
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Grace UwaseJanuary 2016
Experimental Procedure (for the teacher)Start by explaining that we need energy to live, and we get it from what we consume. You can
use a simple demonstration such as a toy car that will not move unless you push it (give it
energy). Mention different macromolecules; carbohydrates, lipids, and proteins, the body needs
and give examples of what foods they come from. When the right food gets in our body, the
body extracts energy from it and what we do not use comes out in form of feces, urine, gas, etc.
The teacher can do a simple breathing exercise and explain that the oxygen goes in and helps the
body to extract the energy, and we exhale CO2 that the body does not need. Explain that the
following experiment will measure the CO2 to determine how much energy a drink gives to the
body.
1) Students will put about 250 mL of each drink in a beaker and heat it up for about 5
minutes. They will transfer the drink to a soda bottle and add 2 teaspoons of yeast, and
immediately cover the bottle with an inflatable glove. They should slide the glove down
past the neck to reduce the surface area inside the glove, and this will allow them to see
the production of gas faster. They should gently swirl the bottle to allow reagents to mix
(caution: this reaction takes long, it would be helpful to get it started and then give
detailed explanations while it runs). Once the reaction is started, talk about the role of
each step in the students just did
Heat: is necessary to make the reaction happen faster
The drink: will be the source of energy
Yeast: contains enzymes that will break down the sugar to release energy and CO2
*Since sugars give energy, discuss different types of sugars and examples of food each sugar
type contains in. For younger kids, the teacher can make paper visuals to ease the discussion.
Carbohydrates are categorized into monosaccharides (example, glucose, fructose, and galactose), oligosaccharides (example sucrose=glucose+fructose, maltose=2 glucose,
lactose=galactose+glucose), and polysaccharides (starch, glycogen, and cellulose =polymers of glucose).
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Grace UwaseJanuary 2016
Let the students predict which drink will give the most energy by doing a hydrometer test.
Before they do the test, let them predict which drink will have the highest sugar (Q1 on
worksheet), and explain to them why hypotheses are important in science.
Each group will take a hydrometer and fill it with their drink all the way up. They will
gently spin the buoy into the liquid to break any surface tension and wait until the buoy
stabilizes. The buoy will float in the drinks at different levels depending on their sugar
content, highest in beverages with highest sugar content. They will record the data.
**Note that the order of sugar content can greatly vary depending on the brand of the
drink, for instance different brands of orange juice could have significantly different
sugar amounts. The given order could change. Now based on the observed sugar content,
let students predict which drink will release the most gas the fastest (Q2).
*Explain that protein is another source of energy. Have the class begin the protein test to see
which drink contains proteins.
Each group will put 1 mL of the drinks in a spot plate and add 1mL of 6 M NaOH,
followed by 1 mL of 20% copper II sulfate solution, and mix with a toothpick. If the
color becomes purple, the drink contains proteins. Remind them to record this on their
worksheet.
*Discuss other things that proteins are useful for, such as catalysis of biological reaction,
supporting living organisms, making up membrane channels and receptors, etc. For advanced
students, a detailed discussion of fermentation vs. respiration, and how the body uses fats and
proteins for energy could be discussed.
At this point, let the students examine the progression of the CO2 gas production. Note that the
order of CO2 production will greatly be affected by the brand of the drink used, how much the
drink was heated, and how much yeast is added. Encourage students to come up with potential
sources of error as part of the Scientific Method of inquiry. In any case, they should observe that
the milk glove is not inflated at all. (If time permits, let the reaction run longer).
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Grace UwaseJanuary 2016
Key: order of drinks, left to right: orange juice, milk, coke, Kool-Aid, Gatorade, Nos energy drink. Coke and Nos energy drink were removed from the experiment because they are carbonated drinks, and the CO2 from carbonation could compromise the CO2 produced from fermentation.
Let the students compare the results to their predictions, and they should note that milk showed
high sugar content, yet no gas was produced. Refer back to the types of sugar discussion, and tell
them that milk contains lactose and the body does not use it for energy as effectively as glucose.
Encourage students to read nutrition value labels to understand what exactly is in their
food/drinks.
Special Notes and Costs: Hydrometers can be purchased from flinnsci.com for about
$33/hydrometer + hydrometer jar. Hydrometers range in prices depending on quality and
function, but for this experiment, only a simple hydrometer is necessary
http://www.flinnsci.com/store/Scripts/prodView.asp?idproduct=18870
Biuret reagent can be made if chemicals are available, but if not, the reagent can be purchased
for $4/30 mL at http://www.hometrainingtools.com/biuret-reagent-30-ml.
*This experiment can be customized to any drink of choice, and the depth of discussion will
depend on the age group. The activity has been done with from 3rd grade (focusing on sugar
types and food groups)–advanced 8th grade (focusing on energy, as well fermentation vs.
respiration, and how the body uses fats and proteins for energy). More tests such as acidity and
starch content can also be easily incorporated.
Sources:"A Safer Biuret Reagent." SSERC. Accessed January 9, 2016.
http://www.sserc.org.uk/index.php/bulletins226/2005/214-spring-2005/1288-a-safer-biuret-reagent291.
"Macromolecules." Accessed January 11, 2016. http://www.austincc.edu/biology/assessment/pdf/Module2_Macromolecules.pdf.
Redstone, Sam (2014) You Are What You Eat Colby College CH 151 website. http://web.colby.edu/ch151/sams-page/
Zamora, Antonio. "Carbohydrates - Chemical Structure." Scientific Psychic. Accessed January 15, 2016. http://www.scientificpsychic.com/fitness/carbohydrates.html.
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Grace UwaseJanuary 2016
High-Speed Energy Worksheet (5th-8th grade)
Name:
1) Predict which drink contains the most and the least amount of sugar.
2) Predict which drink will produce the most gas and explain why.
3) In the table below record your results
Drink Order by how much gas
produced (mark 1for the
most gas, 2 for the second
highest, etc)
Sugar content Contains proteins
(yes or no)
Milk
Orange Juice
Kool-Aid
Getorade
4) Did your results match your predictions? If results did not match predictions, describe
what was different.
5) Based on the experiment, what would be the best drink to give to Jaime? Explain using
our results.
6) Predict what you would see, if we had oil as our 5th drink.
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Grace UwaseJanuary 2016
High-Speed Energy Worksheet (2nd - 4th grade)
Name:
1) Predict which drink contains the most and the least amount of sugar.
2) Predict which drink will produce the most gas.
3) In the table below record your results
Drink Order by how much gas
produced (mark 1for the
most gas, 2 for the second
highest, etc)
Sugar content Contains proteins
(yes or no)
Milk
Orange Juice
Kool-Aid
Gatorade
4) Where is the gas in the glove coming from?
5) Based on the experiment, what would be the best drink to give to Jaime?
6) Did you find anything surprising about this experiment?
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