What Is The Role Of Chlorophyl?

Chlorophyll gives green plants their color.

Chlorophyll is a green pigment that gives plants their characteristic green color. Chemist Paul May, writing on the University of Bristol School of Chemistry website, says that its role in green plants is to power the chemical process called photosynthesis that turns water and carbon dioxide into glucose -- a type of sugar -- and oxygen. Plants use this sugar to power all of their life processes.

Plant Pigments

Pigments are molecules that absorb light. Scientist M. J. Farabee explains on the Estrella Mountain Community College website that the color of any pigment is determined by the color of light that it reflects and does not absorb. Since chlorophyll does not absorb green light waves, it looks green.

Types of Chlorophyll

Farabee says that all plants contain chlorophyll a, which absorbs light from violet-blue and reddish-orange light waves. Accessory pigments such as chlorophyll b and carotenoids can absorb light in the green, yellow and orange wavelengths.

Photosynthesis

According to Farabee, when light strikes chlorophyll, the molecules' electrons become excited and move to a higher energy level. Using water and carbon dioxide present in the plant and the atmosphere, a series of chemical reactions then take place. Molecules are split and reorganized, resulting in the formation of sugar molecules and hydrogen atoms. The waste product from the photosynthesis process, oxygen, is essential to all human and animal life.

References

• University of Bristol School of Chemistry: Chlorophyll
• Estrella Mountain Community College: Photosynthesis