Photosynthesis160-page5 - absorb light and serve as...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Photosynthesis - 5 One can also measure rates of photosynthesis in different wavelengths to generate an action spectrum. This is done by growing plants in light boxes that have just one wavelength of light, or with algae, using a prism to separate light waves passing through a microscope. Action spectra reinforce that photosynthesis occurs more in blue and in red light. 5 . The Light Absorbing Pigments of Photosynthesis Chlorophyll is the primary pigment that absorbs light energy in photosynthesis. In plants, there are two forms of chlorophyll (a, which has a methyl group, and b, which has an aldehyde group). There are also important accessory pigments, the carotenes. Each pigment absorbs certain wavelengths, and collects and concentrates light energy for the photosynthetic process. The red and blue phycocyanin pigments can also
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: absorb light and serve as accessory pigments in photosynthesis. When pigment molecules absorb energy from light, electrons are excited and move to a higher energy level in their excited state. The energy level of the light absorbed (that photon) and the excited energy level state must match, which is why only certain wavelengths can be absorbed by certain pigments. This rise in energy is temporary. Electrons fall back to their original energy level if the energy is not transferred elsewhere. When the electrons fall back to their original level, energy is given off as heat, or sometimes as light (fluorescence). Chlorophyll a does both, fluorescing as red light. Fortunately, in photosynthesis, the electrons are transferred elsewhere and their energy is captured....
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online