1. EOC Review: Plant Puzzler

2. Biology EOC next Thursday!

4. Directions: Use the following information to answer questions 1 through 9.
Demetri did the following investigation in a local college laboratory to see how carbon dioxide (CO2) affects plant growth.
Demetri grew bean plants in growth chambers where he could control the amount of oxygen (O2) and CO2 in the air around the plants. He grew the bean plants in water with mineral nutrients instead of soil. Demetri had to completely dry the plants in an oven to get the plants’ dry mass.
Question: What is the effect of different amounts of carbon dioxide (CO2) in air on the dry mass of bean plants?
Hypothesis: As the concentration of CO2 in air increases, the dry mass of bean plants will increase because bean plants use CO2 for growth.

5. Amount of CO2 vs. Bean Plant Dry Mass Amount of CO2
Procedure:
Put 12 bean plants into Chamber A as shown in the Investigation Setup diagram. Do the same to Chambers B and C.
Make sure each chamber receives the same amount of light and water. Keep the chambers at a constant temperature and pressure.
Adjust the O2 level of the air in each chamber to the normal amount of O2 in the atmosphere.
Remove 4 bean plants from each chamber. Dry the plants in the oven and measure their dry masses.
Calculate and record the average dry masses as Day 1.
Set and keep the CO2 level in Chamber A at 0 parts per million (ppm), Chamber B at 700 ppm, and Chamber C at 1,400 ppm.
Repeat steps 4 and 5 for Day 7 and Day 14.
Amount of CO2 vs. Bean Plant Dry Mass
Amount of CO2
(parts per million)
Bean Plant Dry Mass
(averages in grams)
Day 1
Day 7
Day 14
(Chamber A)
0.8
700
(Chamber B)
4.5
8.6
1,400
(Chamber C)
4.7
10.8
Note: Day 1 masses were determined before CO2 levels were adjusted.

6. 1 What was the manipulated (changed) variable in this investigation?
A. Amount of light
B. Amount of CO2
C. Growth of plants
D. Type of plants

7. Which two variables were controlled (kept the same) variables in this investigation?
A. Final bean plant dry mass and amount of light
B. Amount of CO2 and type of growth chamber
C. Growth of plants and amount of O2
D. Type of plants and amount of O2

8. Which variable was the responding (dependent) variable in this investigation?
A. Hours of light
B. Bean plant dry mass
C. Total days bean plants grew
D. Mineral nutrients in the water
Thing measured

9. Why did Demetri have growth chamber A adjusted to 0 ppm of CO2?
A. To show bean plants can make their own CO2 when none is available
B. To make the bean plants use oxygen for photosynthesis instead of CO2
C. To ensure the amount of CO2 caused the differences in dry mass
D. To demonstrate that CO2 is used by the bean plants for respiration
Amount of CO2 vs. Bean Plant Dry Mass
Amount of CO2
(parts per million)
Bean Plant Dry Mass
(averages in grams)
Day 1
Day 7
Day 14
(Chamber A)
0.8
700
(Chamber B)
4.5
8.6
1,400
(Chamber C)
4.7
10.8
Note: Day 1 masses were determined before CO2 levels were adjusted.
Control group

10. 5 Glucose is produced through the process of photosynthesis
5 Glucose is produced through the process of photosynthesis. What form of energy does the glucose have because of photosynthesis?
o A. Heat
o B. Light
o C. Nuclear
o D. Chemical

11. 6 What could Demetri do to be more certain the results of his experiment are reliable?
o A. Test the reaction with different concentrations of oxygen.
o B. Repeat the experiment the same way.
o C. Increase the volume of water given to plants.
o D. Use a different type of growth chamber.

12. 7 What did Demetri do to make sure the results of his experiment were valid?
o A. Kept all variables the same except for the amount of carbon dioxide each group received.
o B. Gave each group of plants different amounts of oxygen.
o C. Gave group C plants 1,400 ppm of CO2.
o D. Calculated the average dry masses on Day 1.
Fair test

13. Be sure to include all of these in your response!
8 Write a conclusion for this investigation. In your conclusion, be sure to:
Answer the investigative question.
Include supporting data from the Amount of CO2 vs. Bean Plant Dry Mass table.
Explain how these data support your conclusion.
Question: What is the effect of different amounts of carbon dioxide (CO2) in air on the dry mass of bean plants?
Be sure to include all of these in your response!

14. As the CO2 increased, the dry mass of the beans also increased.
8 Write a conclusion for this investigation. In your conclusion, be sure to:
Answer the investigative question.
Include supporting data from the Amount of CO2 vs. Bean Plant Dry Mass table.
Explain how these data support your conclusion.
Question: What is the effect of different amounts of carbon dioxide (CO2) in air on the dry mass of bean plants?
As the CO2 increased, the dry mass of the beans also increased.
Group A, plants with no CO2 mass stayed at 0.8g
Group B plants got 700 ppm of CO2 and went from 0.8 g to 8.6 g
Group C plants got 1,400 ppm of CO2 and went from 0.8 g to 10.8g

15. Amount of CO2 vs. Bean Plant Dry Mass Amount of CO2
(parts per million)
Bean Plant Dry Mass
(averages in grams)
Day 1
Day 7
Day 14
(Chamber A)
0.8
700
(Chamber B)
4.5
8.6
1,400
(Chamber C)
4.7
10.8
Note: Day 1 masses were determined before CO2 levels were adjusted.

16. Be sure to include all of these in your response!
9 Plan a new investigation to answer the new question printed in the box. In your plan, be sure to include:
Hypothesis
Materials
Procedure that includes:
logical steps to do the investigation one responding variable
two controlled variables an experimental control condition
one manipulated variable how often measurements should be taken and recorded
Be sure to include all of these in your response!
Question: What is the effect of different amounts of mineral nutrients on the height
of bean plants grown in CO2 rich atmosphere?
Hypothesis:
Materials:
Procedure: You may use this space for a labeled diagram to support your procedure.

17. Question: What is the effect of different amounts of mineral nutrients on the height
of bean plants grown in CO2 rich atmosphere?
Hypothesis: I believe the more mineral nutrients, the taller the plant will grow because plants need mineral nutrients to grow. So the more nutrients, the better.
Materials: bean plants (all same size), water, planting pots (all same with same soil),
Lights (all same), ruler
Procedure: You may use this space for a labeled diagram to support your procedure.
  light
Group A Group B Group C Group D
No nutrients tsp. nutrients tsp. nutrients tsp. nutrient
1. Put 3 bean plants in 4 different groups A, B, C, and D.
2. Make sure each group gets the same amount of water and light, same soil
3. Use ruler to record the height of all of the plants.
4. Give group B plants 1 tsp. of nutrients, group C 2 tsp., and group D 3 tsp. No nutrients for group A.
5. Record height of plants every day for 3 weeks. Compare heights.
6. Repeat experiment 3 more times.