1. Comparing Photosynthesis and Respiration
The most important chemical reaction in the world is…
PHOTOSYNTHESIS
The chemical reaction for photosynthesis is
6CO2 + 6H2O + energy C6H12O6 + 6O2

2. Comparing Photosynthesis and Respiration
Sugar
Carbon Dioxide
6CO2 + 6H2O + energy C6H12O6 + 6O2
Oxygen
Water
Sunlight

3. Comparing Photosynthesis and Respiration
Stage 1
Chlorophyll in the Chloroplasts captures sunlight

4. Comparing Photosynthesis and Respiration
Stage 2
The cell uses the captured sunlight, carbon dioxide and water to make food

5. Comparing Photosynthesis and Respiration
Stage 2
Carbon Dioxide enters the plant through Stomata -small openings on the underside of the leaf

6. THE PHOTOSYNTHESIS - RESPIRATION CYCLE
COMPARING PHOTOSYNTHESIS AND RESPIRATION
THE PHOTOSYNTHESIS - RESPIRATION CYCLE
PHOTOSYNTHESIS
RESPIRATION
Plants Produce
Sugar
Oxygen
Organisms Use
Carbon Dioxide
Water
Energy
Plants use
Organisms Produce

7. Comparing Photosynthesis and Respiration
The process by which cells obtain energy from glucose
RESPIRATION
The chemical reaction for respiration is
C6H12O6 + 6O CO2 + 6H2O + energy

8. Comparing Photosynthesis and Respiration
Oxygen
Carbon Dioxide
C6H12O6 + 6O CO2 + 6H2O + energy
Water
Sugar

9. Comparing Photosynthesis and Respiration
Stage 1
Takes place in the cytoplasm
Molecules of glucose are broken down into smaller molecules
Oxygen is NOT involved
Small amount of energy is released

10. Comparing Photosynthesis and Respiration
Stage 2
Takes place in the Mitochondria
Small molecules are broken down into even smaller molecules
Oxygen is required
A great deal of energy is released
Carbon dioxide and water are also produced

11. THE PHOTOSYNTHESIS - RESPIRATION CYCLE
COMPARING PHOTOSYNTHESIS AND RESPIRATION
THE PHOTOSYNTHESIS - RESPIRATION CYCLE
PHOTOSYNTHESIS
RESPIRATION
Sugar
Oxygen
Plants Produce
Sugar
Oxygen
Organisms Use
Carbon Dioxide
Water
Energy
Organisms Produce
Plants use
Carbon Dioxide
Water
Energy

12. THE PHOTOSYNTHESIS - RESPIRATION CYCLE
COMPARING PHOTOSYNTHESIS AND RESPIRATION
THE PHOTOSYNTHESIS - RESPIRATION CYCLE
PHOTOSYNTHESIS
Plants Produce
Sugar
Oxygen
Carbon Dioxide
Water
Energy
Plants use

13. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Elodea – a common water plant
Elodea releases bubbles of oxygen as it photosynthesizes
Freshly cut Elodea stems produce more bubbles than the leaves

14. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Materials
Elodea Plants
Scissors
Large Container
Clear test tube
Water
Sunlight

15. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Procedures
Fill the large container half full of water
Cut the stem of the Elodea plant at an angle (for greater surface area)

16. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Procedures
Insert the plant, cut stem first, into the test tube
Fill the test tube to overflowing with water

17. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Procedures
Cover the top of the test tube with your thumb
Invert the test tube over the beaker and put the test tube with your thumb still covering the opening into the beaker

18. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Procedures
Release your thumb and gently settle the test tube on the bottom of the container
Place the beaker and test tube in sunlight or under a bright lamp

19. Comparing Photosynthesis and Respiration
Testing Photosynthetic Rate of Elodea
Procedures
At 5 minute intervals for a total of 15 minutes, record the number of bubbles produced
Make a graph of your findings
Have someone in your group report out to the class

20. THE PHOTOSYNTHESIS - RESPIRATION CYCLE
COMPARING PHOTOSYNTHESIS AND RESPIRATION
THE PHOTOSYNTHESIS - RESPIRATION CYCLE
RESPIRATION
Sugar
Oxygen
Organisms Use
Organisms Produce
Carbon Dioxide
Water
Energy

21. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Bromthymol Blue (BTB)
An acid-base indicator that can be used to measure levels of carbon dioxide (CO2)
BTB changes color from blue to green and then yellow as it gets more acidic

22. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Bromthymol Blue (BTB)
If carbon dioxide is added to the solution it will become more acidic and change color moving to green and then yellow
If carbon dioxide is removed from the solution it will become more basic and change color moving to blue

23. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
This experiment uses Bromthymol Blue to examine the relationship between exercise and the amount of carbon dioxide you produce

24. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Materials
2 straws
2 plastic cups
Timer
Bromthymol Blue solution
Paper towels

25. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Label one cup “1” and the other cup “2”
Fill both cups to the marked line with BTB

26. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Record the color in both cups on your lab sheet
Place a straw in cup 1

27. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Have a group member blow through the straw into the solution until it changes color
Have a group member time how long it takes for the solution to change color

28. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Record how long it took for the solution to change color on your lab sheet
Remember the solution is changing color because you are exhaling carbon dioxide into it

29. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Predict how long it would take the solution to change color after exercise
Record your prediction on your lab sheet

30. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Design an experiment to test your prediction
This means a group member must do some form of exercise (like jumping jacks)

31. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
The exercise should be something you can do “in place” near your tables
Only one group member will perform the exercise

32. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Write down the steps of your experiment
Get your teacher’s approval BEFORE you begin your experiment

33. Comparing Photosynthesis and Respiration
Respiration and Carbon Dioxide
Procedure
Follow the directions in the Analyze and Conclude section of your lab sheet to conduct your experiment and record your results