Electromagnetic spectrum involved in photosynthesis
Wavelengths
Absorbtion of pigments
- Plants use visible light (400 nm to 700 nm) for growth and photosynthesis.
- The wavelength of red light is about 650 nm.
- Green light has a wavelength of about 510 nm, and the wavelength of blue light is about 475 nm.
- Photosynthesis depends on on the absorption of light by pigments in the leaves of plants. The most important of these pigments is chlorophyll-a.
Photosynthesis
- Photosynthetic organisms contain light-absorbing molecules called pigments that absorb only specific wavelengths of visible light, while reflecting others.
- The set of wavelengths absorbed by a pigment is its absorption spectrum
- Most photosynthetic organisms have a variety of different pigments, so they can absorb energy from a wide range of wavelengths
- Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.
- Plants, are experts at capturing light energy and using it to make sugars through a process called photosynthesis.
- This process begins with the absorption of light by specialized organic molecules, called pigments, that are found in the chloroplasts of plant cells.
Light energy
Chlorophylls
Light is a form of electromagnetic radiation, a type of energy that travels in waves. Other kinds of electromagnetic radiation that we encounter in our daily lives include radio waves, microwaves, and X-rays. Together, all the types of electromagnetic radiation make up the electromagnetic spectrum.
- In plants, chlorophyll a and chlorophyll b are the main photosynthetic pigments.
- Chlorophyll molecules absorb blue and red wavelengths
- Because of the central role of chlorophyll a in photosynthesis, all pigments used in addition to chlorophyll a are known as accessory pigments
- Accessory pigments allows a broader range of wavelengths to be absorbed, and thus, more energy to be captured from sunlight.