Chlorophyll

Chlorophyll at different scales
Lemon balm leaves
Chlorophyll is responsible for the green color of many plants and algae.
A microscope image of plant cells, with chloroplasts visible as small green balls
Seen through a microscope, chlorophyll is concentrated within organisms in structures called chloroplasts – shown here grouped inside plant cells.
A leaf absorbing blue and red light, but reflecting green light
Plants are perceived as green because chlorophyll absorbs mainly the blue and red wavelengths but green light, reflected by plant structures like cell walls, is less absorbed.[1]
The structure of chlorophyll d
There are several types of chlorophyll, but all share the chlorin magnesium ligand which forms the right side of this diagram.

Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants.[2] Its name is derived from the Greek words χλωρός (khloros, "pale green") and φύλλον (phyllon, "leaf").[3] Chlorophyll allows plants to absorb energy from light.

Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion.[4] Conversely, it is a poor absorber of green and near-green portions of the spectrum. Hence chlorophyll-containing tissues appear green because green light, diffusively reflected by structures like cell walls, is less absorbed.[1] Two types of chlorophyll exist in the photosystems of green plants: chlorophyll a and b.[5]

  1. ^ a b Virtanen O, Constantinidou E, Tyystjärvi E (2020). "Chlorophyll does not reflect green light – how to correct a misconception". Journal of Biological Education. 56 (5): 1–8. doi:10.1080/00219266.2020.1858930.
  2. ^ May P. "Chlorophyll". University of Bristol.
  3. ^ "chlorophyll". Online Etymology Dictionary.
  4. ^ Muneer S, Kim EJ, Park JS, Lee JH (March 2014). "Influence of green, red and blue light emitting diodes on multiprotein complex proteins and photosynthetic activity under different light intensities in lettuce leaves (Lactuca sativa L.)". International Journal of Molecular Sciences. 15 (3): 4657–70. doi:10.3390/ijms15034657. PMC 3975419. PMID 24642884.
  5. ^ Speer BR (1997). "Photosynthetic Pigments". UCMP Glossary (online). University of California Museum of Paleontology. Retrieved 2010-07-17.