Why is phenol red a good indicator of photosynthesis?
Explain why Phenol red is a good indicator of photosynthesis? Phenol red turns red in basic (and neutral) solutions: photosynthesis should remove CO2 (carbonic acid) and increase pH (red).
How does CO2 affect phenol red?
Phenol red is red in neutral or basic solutions. As you blow, you will be adding carbon dioxide from your breath to the solution. This will cause the solution to become acidic as the carbon dioxide dissolves in the water, forming carbonic acid. Continue to blow until the phenol red solution turns yellow.
Why can a pH indicator be used to assay for photosynthesis?
Most forms of photosynthesis release oxygen as a byproduct. This is a pH indicator. Because photosynthesis uses CO2 to make energy in the presence of light and chlorophyll. Therefore, resulting in the water becoming less acidic and more basic.
What color will the test tube change when photosynthesis happens?
Test tube C, with the BTB and carbon dioxide only, changed from yellow to blue. investigation? In test tube A, the plant went through photosynthesis in the light and used the carbon dioxide to change it to oxygen so the BTB turned from yellow to blue….
| Start | After 48 Hours |
|---|---|
| A B C | A B C |
How is phenol red used in photosynthesis?
Phenol red, a carbon indicator solution, is used to demonstrate that plants fix carbon during photosynthesis. We often see the process of photosynthesis written as one giant reaction: CO2 + H20 + light → C6H12O6 + O2. As the instructor, you supply the carbon source by blowing bubbles in phenol red.
Why is phenol red added to the test tubes?
Why is phenol red added to the test tubes? Phenol red is a pH indicator. It changes wit the color of the pH.
What does phenol red indicate?
Most commonly, phenol red is an indicator dye, used as an acid pH indicator with a transition point of 7.5 (acid side to yellow / alkaline side to red) Biologists use phenol red in cell cultures as a pH indicator. Phenol red has been used in the PSP test for kidney functions.
Why would the phenol red solution in the tube change color over time?
Phenol red is yellow under acidic conditions (high H ion concentration), pink under basic or alkaline conditions (low H ion concentration) and orange under neutral conditions. If the CO2 concentration decreases, the H ion concentration will also decrease and the solution will change to pink, becoming basic.
Which pigment is necessary for photosynthesis?
Chlorophyll
Chlorophyll, the primary pigment used in photosynthesis, reflects green light and absorbs red and blue light most strongly. In plants, photosynthesis takes place in chloroplasts, which contain the chlorophyll.
What color is BTB during photosynthesis?
Bromothymol blue solution, BTB, can indicate the presence of carbon dioxide in the water. When little or no carbon dioxide is present, BTB will show a blue color. Depending upon the amount of carbon dioxide, BTB will change to green or yellow. Yellow indicates more carbon dioxide.
What is the purpose of phenol red?
Phenol red is a water-soluble dye used as a pH indicator, changing from yellow to red over pH 6.6 to 8.0, and then turning a bright pink color above pH 8.1. As such, phenol red can be used as a pH indicator dye in various medical and cell biology tests.