activity page will offer:
in bone composition and physiology
opportunity to compare and contrast the decalcifying properties
of several liquids
- old chicken bones (boiled with all meat removed)
- vinegar (0.4% acetic acid)
- dilute hydrochloric acid solution (0.2%) *see teacher
- window washing solution (ammonia based)
- alcohol (methanol or ethanol)
- distilled water
- safety goggles
- protective apron
- 5 jars with lids
1 - Dissolving Minerals
with a partner.
- Obtain five chicken bones that have been stripped of
- Put on your safety goggles and protective apron
- Label five jars: water, alcohol, HCl, window cleaner,
and vinegar. What do you know about each of these liquids?
Which ones are acids? Which ones are bases? Which ones
- Fill these jars halfway with the identified liquids.
NOTE: The jars must contain enough liquid so that the
entire bone sample will be immersed.
- Examine each of your five bone samples. Describe their
physical appearance and properties.
Are the bones hard or soft?
Do the bones bend and twist easily or are they too rigid
- Use forceps to place one bone into each solution.
- Cover each jar with a lid. Place it in a secure area
identified by your instructor.
- Make a guess.
Which of these solutions will affect the hardness and
rigidity of the bone? Record your prediction.
- Several days later collect the jars. Put on safety goggles
and a protective apron. Use your forceps to remove the
bones from the liquid.
- Rinse the bones thoroughly in water. Let them soak in
a water bath for several minutes. Rinse them again.
- When your instructor has given the approval, you may
test the bones for any changes. Try twisting and bending
the bones. Can any of these bones be tied into a knot?
How did your predictions compare with the results you
- Share your results with other teams.
Did all the groups obtain the same results?
Explain any observed differences in bone changes.
- Which solutions softened the bones?
- Why did these solutions affect the property of the bone
- How were the bone-weakening solutions similar?
- What was the purpose of putting one of the bones in
WHAT YOU'VE DONE
can this laboratory experience be applied to the challenges
of extended space flight?
Like bone, marble statues are made of a calcium compound.
Using your equipment from the previous experiment, design
and carry out an experiment to determine the effects of
acids and other solutions on marble chips. Don't forget
to use a control such as water that will not react with
Think of some other reasons why people might experience
bone decalcification. What can this experiment teach you
about osteoporosis in older people, or the importance of
good nutrition in children?
This is a rich site on cell growth, osteoporosis, and bones
The medical challenges awaiting the Mars journey.
NASA site on the musculoskeletal concerns of shuttle missions.
Matters" and "Getting the Minerals Out" 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).