In the leaf disk assay, what is the purpose of adding baking soda to the water?

To provide a source of carbon dioxide for the leaves.

Why is it important to use a consistent wattage light source when comparing photosynthetic rates in different experimental setups?

To ensure that light intensity is not a variable affecting the rate of photosynthesis.

Grade 9th Grade · Science · 60 min

I can relate changes in BTB color to the rate of photosynthesis.

LabXchange · 8:09

Measuring Photosynthesis: Leaf Disk Assay

3 key concepts

1
Photosynthesis is the process where plants use energy from the sun to convert water and carbon dioxide into sugars, releasing oxygen in the process.
2
In the leaf disk assay, leaves are infiltrated with water under a vacuum to make them sink, and then the rate at which they float again due to oxygen production is measured to estimate photosynthetic rate.
3
A control group without carbon dioxide is used to compare against the experimental group with carbon dioxide, ensuring that any observed flotation is due to photosynthesis.

12 questions · Multiple choice & Short answer

Quick comprehension check

“In the leaf disk experiment, what color would the solution be if photosynthesis is occurring at a high rate, and why?”

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