1. Photosynthesis Lab
Using the Floating Disk Method to show if light is needed for photosynthesis

2. Identify the Leaf Structures

3. Here are the structures…
What structures are needed for photosythesis?
Here are the structures…
What is the function of the stoma and guard cells?

4. How did you get the leaf disks to sink?
Watch how to make the leaf disks sink?

5. Before
After
Where’s the light?

6. Check out the floating leaf disks…
Notice the oxygen bubbles coming from the leaf disks. Why? Photosynthesis is producing oxygen which fills up the air spaces and causes the leaf disk to float.

7. Data for the Lab….
With light
No light

8. Can you graph the data?

9. Can you figure out what was being studied here?
What was the variable?

10. Be sure you can answer these two questions…
According to your data, does light affect the ability or rate of photosynthesis? Explain your answer using the data you collected.
Why is photosynthesis considered a “light dependent” reaction? Explain.

11. Questions are due at a certain time in the period.
Post Lab Assignment:
Use your notes and data.
Quietly and thoughtfully work with your partner.
Both partners are to complete the questions quietly and thoughtfully.
Decide which partner will be the “writer of the answers”
Decide which partner will be the “speaker of the answers”
Questions are due at a certain time in the period.