Home > categories > Lights & Lighting > Garden Lights > How does light affect photosynthesis?
Question:

How does light affect photosynthesis?

title. like the visible light spectrum

Answer:

More light means more photosynthesis, to the point of light saturation. Then photosynthesis declines because of thermal inhibition.
I just answered this question. Go to your other question.
photosynthesis is the process by which light is stored as sugar that the plant can use for energy, so the more light , the faster the plant can photosynthesise until it becomes limited by another factor required for photosynthesis (like water, temperature ect)
Plants need the full visible spectrum to grow well. Though their range of collection spans the wavelengths 300-800nm plants collect most strongly at certain bands rather than equally at every wave length. Chlorophylls, the primary photosynthetic pigment class, includes Chlorophyll a absorbing strongest in the red and Chlorophyll b absorbing most in the blue. Together the chlorophyll absorbs wavelengths of visible light except across a shared 'green gap' that is reflected. 400nm < Chlorophyll's strongest absorption < 700 nm. Below 400nm the higher energy of the photons raise the risk of photochemical damage. Beyond 700 nm the energy levels are insufficient to effectively drive photochemistry for most organisms (except in cyanobactria with chlorophyll d p740). This puts the most usable energy in the visible lengths. First life was aquatic where light in higher energy states does not penetrate far. So light absorption under water is best in the long penetrating red wavelengths where chlorophyll a mostly absorbs. The various accessory pigments arose later to capture the high energy blue light and to fill the green gap in differing niches. For example chlorophyll b extends the absorption range by about 30nm into the 'green gap' reducing the range of reflected light in plants when chlorophyll a/b are present in photosystem II. Chl b’s main function is to collect energy but a secondary function is to regulate the primary antenna size. Chl b is not the only accessory pigment nor was likely the the first. Photosynthetic accessory pigments include many carotenoids, chlorophylls other than chl a and the phycobilins common to the cyanobacteria (bluegreen algae) rhodophyta (red algae).

Share to: