THE DEMISE OF A HALLOWEEN PUMPKIN
T. Holtzclaw
(High energy / complex molecules vs insects, nematodes, fungi, protozoans, bacteria, etc.)
Scenario: We will observe two pumpkins. One will be a whole uncut pumpkin
(this will be our control). The other will be a freshly carved pumpkin
(carved = experimental factor). The two pumpkins will be placed side by side
on a plastic tray in our classroom. We will observe these pumpkins for approximately
three months. You will keep a log on the pumpkins. Your log should note all changes,
organisms and events that occur over the next three months. Each day's entry should be
divided into quantitative and qualitative observations. You should make
at least two entries a week (Mon. and Fri.?). You may enter more entries if you choose
to do so. You will be given two classroom sessions with your microscopes to observe
any microscopic structures and/or organisms. You are also welcome to come in before
(6:45 am) and/or after(up to 5:00 pm) school on your own time to make any additional
observations. In making your observations, try to use as many of your senses as you can. Do not eat or taste the pumpkins. Be sure to include observations such as: mass (teacher will weigh pumpkins once a week), height, width, colors, smells, textures, physical state(s), sounds(?), temperatures(room, pumpkin and pumpkin fluids) and any others that you think might be appropriate. The instructor will take pictures of the pumpkins twice a week. These will be posted for the students.
SCORING:
- "Day One" description (10 points) _______
- Logs, "At least twenty entries" (60 points) _______
- Organism drawings, "At least four drawings" (20points) _______
- Questions (20 points) _______
- "Final Day" description (10 points) _______
- Suggestions for the improvement of this activity (10 points) _______
- Your thoughts and reflections on this activity (10 points) _______
- Bonus Points!!! (up to 14 points) _______
(Neatness, data records, graphs, daily logs, notes, conclusions, etc.)
- Total points possible: 140 + bonus points _______
Log format:
Day #: ________ Date:______/______/_______ Observations:
The Demise Of A Halloween Pumpkin
(Some questions for thought and POINTS)
- Why does the carved pumpkin rot and breakdown? (Give at least four specific reasons)
- Why does the uncarved pumpkin remain the same?
- How long do you think that the uncarved pumpkin will remain intact and healthy?
Why?
- What is the rotting pumpkin changed into? (think in terms of organisms and by-products.)
- Where did the energy in the pumpkin originally come from?
- What two compounds where used to make over 98% of the pumpkin's mass?
A. _______________________________
B. _______________________________
- Name four food products that are made from pumpkins.
A. _________________________
B. _________________________
C. _________________________
D. _________________________
- Name four different ways that we preserve food.
A. ___________________________
B. ___________________________
C. ___________________________
D. ___________________________
- Explain, physiologically, how any two of the above (item #8) preserve food.
A.
B.
- Design a simple experiment that we could do with Halloween pumpkins.
(use back if necessary)
The Demise Of A Halloween Pumpkin
Some questions for thought and for POINTS
ANSWER KEY
- Why does the carved pumpkin rot and breakdown? (Give at least four specific reasons)
A. Other organisms (fungi, bacteria, protozoans, insects, etc.) can now enter easily and steal the
stored up high energy molecules of the pumpkin. This process is called rotting.
B. Oxygen can easily enter and cause oxidation.
C. Dehydration will begin when the pumpkin is carved. Low humidity?
D. Light can now enter as well as dust and other particles.
- Why does the uncarved pumpkin remain the same?
It is sealed against germs and
dehydration
- How long do you think that the uncarved pumpkin will remain intact and healthy? (Your guess)
Why?(The student should give some reason for her or his guess.)
- What is the rotting pumpkin changed into? (think in terms of organisms and by-products.)
Essentially the pumpkin will adventually turn into H2O and CO2.
- Where did the energy in the pumpkin originally come from? The sun!
- What two compounds where used to make over 98% of the pumpkin's mass?
A. WATER B. CARBON DIOXIDE
- Name four food products that are made from pumpkins.
A. PIES
B. COOKIES C. BREAD D. VEGETABLE
- Name four different ways that we preserve food.
A. LOW TEMPERATURES, FREEZERS AND REFRIGERATORS
B. HEAT and SEAL, "CANNING". C. HYPERTONIC ENVIRONMENT,SUGAR and SALT D. RADIATION E. DEHYDRATION F. POISONS. OTHERS?
- Explain, physiologically, how any two of the above (item #8) preserve food.
A. Low temps=
stops biochemistry. B. Heat and seal =kills and seals C.
Hypertonic = Draws water out of germs.
D. Radiation= kills germs. E. Dehydration = no life. F. poison (preservatives) = kills germs
- Design a simple experiment that we could do with Halloween pumpkins.
Some areas for thought: Humidity, light, temperature, types of organisms, degree of cutting on the outside of the pumpkin.
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