Absorption and Action spectra

Absorption spectrum

A graph showing the percentage of light absorbed at each wavelength by a pigment or a group of pigments

Action spectrum

shows the rate of photosynthesis at each wavelength of light

Similarities between absorption and action spectra

Both involve wavelengths of light
peaks in blue and red regions
low activity in green region

What does the overlap between absorption and action spectra highlight

the efficiency of chlorophyll in capturing light energy for photosynthesis

What does the absorption spectrum measure?

Light absorption by pigments

What does the action spectrum measure?

Rate of photosynthesis

What is the data source for the absorption spectrum and action spectrum

Individual pigments
Combined effect of all pigments and photosynthetic machinery

Why is the action spectrum broader than the absorption spectrum?

It includes contributions from accessory pigments like carotenoids, which absorb light where chlorophyll is less effective.

How can oxygen production be measured?

Oxygen sensor
Counting bubbles produced during photosynthesis

How can carbon dioxide consumption

observing changes in pH