activity page will offer
overview of diabetes
hands-on activity using a sugar indicator solution
activity to determine relative amounts of sugar in several
- Benedicts reagent (available through school catalogs
or at local pharmacies)
- Scale illustrating colors and associated sugar concentrations
- Beaker, size 1000 ml
- Test tubes
- Test tube holder
- Graduated cylinder, size 10 ml or 100 ml
- Lime juice
- White grape juice
- Grapefruit juice
- Apple juice
- Protective goggles
- Boiling water bath
- Put on your safety goggles and adhere to all laboratory
precautions addressing the use of a boiling water bath.
- Add 4 mL of white grape juice to your test tube.
- Add 1 mL of Benedict's solution to the juice. Swirl the
tube to ensure that it
- mixes well.
- With your instructor's approval, place your test tube
in the boiling water bath.
- Wait several minutes or until the color change is complete
(blue color may turn to green, yellow. orange, red, brown).
Examine and compare the color of the solution to reference
color sheet. Record the relative concentration of sugar.
- Test the other juice samples in the same manner. Record
all results in a data table.
- What did the Benedict's solution test for?
- How did the presence of a reducing sugar affect the Benedict's
- What color would the Benedict's display if there was no
sugar in the solution?
- What color would the Benedict's display if it tested a
sugar (sucrose) solution?
- Did these juices contain reducing sugars? How could you
- Which juice underwent the most dramatic color shift? Why?
- Which juice underwent the least change in color? Why?
molecular formula for glucose is .
Five of the carbons and one oxygen atom are joined together
in a ring structure. The other carbon is attached to one of
the ring carbons that is located next to the ring oxygen.
The remaining five oxygen atoms are joined to hydrogen atoms
to form OH groups. From this information and a supply of gumdrops
and toothpicks, construct the glucose molecule.
SWEET MATH CONNECTION
scale illustrates the relative sweetness of several sugars
sucrose = 100
Lactose (complex sugar) = 16
Galactos (simple sugar) =32
Sucrose (complex sugar) =100
Fructose (simple sugar) =173
this scale, answer the following questions:
- Which is the sweetest of these four sugars?
- How many times sweeter is sucrose than lactose?
- How many grams of fructose would be needed to replace
10 grams of sucrose in order to produce the same sweetness?
- Suppose a recipe calls for 5 grams of sucrose to sweeten
a dish. How much lactose would be needed if you substituted
Diabetes is a chronic disorder that results in an increased
level of sugar (glucose) in the bloodstream. It is caused
by the inadequate production or use of insulin, a hormone
produced within the pancreas that allows the body to use and
store glucose. With an insufficient level of this hormone,
high levels of sugar remain in the blood resulting in symptoms
including increased urine production and excessive thirst.
The body responds to the low insulin levels by breaking down
fat and producing damaging metabolic bi-products called ketones.
Diabetes may be regulated by regular doses of insulin, which
quickly lowers the blood sugar level. If, however, the level
of insulin is too high, excessive sugar is removed from the
blood. In order to regain this delicate sugar balance, an
individual may require a quick "fix" of sugar that is available
in orange juice and other sweet liquids.
a diabetic has a low blood sugar level, that person may
drink orange juice. Orange juice contains a high concentration
of sugar that is readily used by the body. In contrast,
some foods contain sugars that must be broken down before
they can be used. These slow-release sugars may offer a
diabetic a window in which a compromised insulin response
has sufficient time to deal with the slowly rising sugar
level. Think about it. Should a diabetic who is suffering
from low sugar levels be given a food containing a slow-release
the Hunter/Gatherers Ate
A review of Paleolithic nutrition
An interactive, multiple-choice diabetes test
database for all foods maintained by the USDA
A sophisticated diabetes software simulator program
activities in this guide were contributed by Michael DiSpezio,
a Massachusetts-based science writer and author of "Critical
Thinking Puzzles" and "Awesome Experiments in Light & Sound"
(Sterling Publishing Co., NY).
Advisors for this Guide:
Corrine Lowen, Science Department, Wayland Public Schools,
Suzanne Panico, Science Department, Fenway High School, Boston,
Anne E. Jones, Science Department, Wayland Middle School,