Contents
How does the spectrophotometer measure photosynthesis?
To measure the percentage of each wavelength of light absorbed by a pigment (the absorption spectrum), a spectrophotometer is used. The spectrophotometer measures the increase in light transmittance over time, and thus indicates the rate of photosynthesis.
What is the purpose of using DPIP in this experiment?
The purpose of the DPIP in the experiment is to be the electron acceptor. DPIP, generally blue, becomes colorless as it gains electrons and is reduced. This change in color indicates photosynthesis is occurring.
How does absorbance relate to photosynthesis?
Pigments absorb light used in photosynthesis. In photosynthesis, the sun’s energy is converted to chemical energy by photosynthetic organisms. The set of wavelengths absorbed by a pigment is its absorption spectrum.
What is DPIP test?
The first stage, called the light reactions of photosynthesis, requires light energy. In this experiment, a blue dye (2,6-dichlorophenol-indophenol, or DPIP) will be used to replace NADPH in the light reactions. When the dye is oxidized, it is blue. When reduced, however, it turns colorless.
What color do plants reflect?
green color
Chlorophyll gives plants their green color because it does not absorb the green wavelengths of white light. That particular light wavelength is reflected from the plant, so it appears green. Plants that use photosynthesis to make their own food are called autotrophs.
What molecule does DPIP replace?
Since DPIP replaces NADPH in the light reactions, it will turn from blue to colorless when reduced during photosynthesis. This will allow you to monitor the rate of photosynthesis. In order to allow the DPIP to come into contact with chloroplasts, the cells will need to be carefully disrupted.
What is the purpose of DPIP in the experiment?
Is this an AP lab?The DPIP replaces NADP+.In photosynthesis, NADP is reduced to NADPH, but NADP is colorless.DPIP replaces the NADP. When DPIP is reduced, it changes from blue to clear. DPIP is used to show photosynthesis taking place. What molecule found in chloroplast does DPIP replace in this experiment? if you are referring to AP bio lab 4…
How is the rate of photosynthesis and respiration measured?
Using ‘immobilised algae’ – It’s easy and accurate to measure the rate of photosynthesis and respiration using immobilised algae in hydrogen carbonate indicator solution – known as the ‘algal balls’ technique. Read the full protocol on using immobilsed algae to measure photosynthesis.
Why does DPIP change from blue to colorless?
Boiling chloroplasts prevents the DPIP from being reduced because the enzymes for photosynthesis are no longer present in the chloroplasts. DPIP is reduced from blue to colorless when light strikes the chloroplasts and the electrons are boosted to a higher energy level.
How to measure the rate of photosynthesis in pondweed?
Read a full protocol on how to investigate photosynthesis using pondweed. There is a crude method where a disc is cut out of one side of a leaf (using a cork borer against a rubber bung) and weighed after drying. Some days (or even weeks later), a disk is cut out of the other half of the leaf, dried and weighed.