chlorophyll

Examples of chlorophyll in the following topics:

• Absorption of Light

  • Pigments, like chlorophyll and carotenoids, absorb and reflect light at a certain region of the electromagnetic spectrum.
  • There are five major chlorophylls: a, b, c and d, along with a related molecule found in prokaryotes called bacteriochlorophyll.
  • Chlorophyll a absorbs light in the blue-violet region, while chlorophyll b absorbs red-blue light.
  • Neither a or b absorb green light; because green is reflected or transmitted, chlorophyll appears green.
  • (a) Chlorophyll a, (b) chlorophyll b, and (c) β-carotene are hydrophobic organic pigments found in the thylakoid membrane.

• Streptophytes and Reproduction of Green Algae

  • Green algae contain the same carotenoids and chlorophyll a and b as land plants, whereas other algae have different accessory pigments and types of chlorophyll molecules in addition to chlorophyll a.

• Main Structures and Summary of Photosynthesis

  • In multicellular autotrophs, the main cellular structures that allow photosynthesis to take place include chloroplasts, thylakoids, and chlorophyll.
  • Embedded in the thylakoid membrane is chlorophyll, a pigment that absorbs certain portions of the visible spectrum and captures energy from sunlight.
  • Chlorophyll gives plants their green color and is responsible for the initial interaction between light and plant material, as well as numerous proteins that make up the electron transport chain.

• Processes of the Light-Dependent Reactions

  • Each photosystem consists of multiple antenna proteins that contain a mixture of 300–400 chlorophyll a and b molecules, as well as other pigments like carotenoids.
  • The two photosystems absorb light energy through proteins containing pigments, such as chlorophyll.
  • When a chlorophyll a molecule within the reaction center of PSII absorbs a photon, the electron in this molecule attains a higher energy level.
  • Pigments in the light-harvesting complex pass light energy to two special chlorophyll a molecules in the reaction center.
  • The light excites an electron from the chlorophyll a pair, which passes to the primary electron acceptor.

• The Two Parts of Photosynthesis

  • In the light-dependent reactions, energy from sunlight is absorbed by chlorophyll and converted into stored chemical energy, in the form of the electron carrier molecule NADPH (nicotinamide adenine dinucleotide phosphate) and the energy currency molecule ATP (adenosine triphosphate).
  • Pigments in the light-harvesting complex pass light energy to two special chlorophyll a molecules in the reaction center.
  • The light excites an electron from the chlorophyll a pair, which passes to the primary electron acceptor.

• Essential Nutrients for Plants

  • Iron (Fe) is essential for chlorophyll synthesis, which is why an iron deficiency results in chlorosis.
  • Manganese (Mn) activates some important enzymes involved in chlorophyll formation.
  • Zinc (Zn) participates in chlorophyll formation and also activates many enzymes.

• Nutrients from Other Sources

  • A saprophyte is a plant that does not have chlorophyll, obtaining its food from dead matter, similar to bacteria and fungi.
  • Saprophytes, like this Dutchmen's pipe (Monotropa hypopitys), obtain their food from dead matter and do not have chlorophyll.
  • The dodder has no chlorophyll and cannot produce its own food.

• Plant Responses to Light

  • In terrestrial habitats, light absorption by chlorophylls peaks in the blue and red regions of the spectrum.

• Comparing Plant and Animal Cells

  • The chloroplasts contain a green pigment called chlorophyll, which captures the light energy that drives the reactions of photosynthesis.
  • Some bacteria perform photosynthesis, but their chlorophyll is not relegated to an organelle.

• The Chemical Basis for Life

  • Carbon exists in many forms in this leaf, including in the cellulose to form the leaf's structure and in chlorophyll, the pigment which makes the leaf green.