Scientists Say: Chlorophyll | Science News for Students

Scientists Say: Chlorophyll

These pigments help make the world green
Sep 26, 2016 — 7:00 am EST

These cells are filled with tiny round chloroplasts — structures containing the pigment chlorophyll.

Kristian Peters/Wikimedia Commons/ (CC BY-SA 3.0)

Chlorophyll (noun, “CHLOR-oh-fill”)

This is a word used to describe several kinds of green pigments in plants. They are often contained in structures called chloroplasts. These green pigments use sunlight to make energy out of carbon dioxide and water. In the process, they produce oxygen — something we all need to get by.

In a sentence

Scientists were able to identify algae in a photograph taken from space using the chlorophyll and other pigments inside the cells.

Power Words

(for more about Power Words, click here)

algae     Single-celled organisms, once considered plants (they aren’t). As aquatic organisms, they grow in water. Like green plants, they depend on sunlight to make their food.

carbon     The chemical element having the atomic number 6. It is the physical basis of all life on Earth. Carbon exists freely as graphite and diamond. It is an important part of coal, limestone and petroleum, and is capable of self-bonding, chemically, to form an enormous number of chemically, biologically and commercially important molecules.

carbon dioxide     (or CO2) A colorless, odorless gas produced by all animals when the oxygen they inhale reacts with the carbon-rich foods that they’ve eaten. Carbon dioxide also is released when organic matter (including fossil fuels like oil or gas) is burned. Carbon dioxide acts as a greenhouse gas, trapping heat in Earth’s atmosphere. Plants convert carbon dioxide into oxygen during photosynthesis, the process they use to make their own food.

chlorophyll     Any of several green pigments found in organisms that perform photosynthesis — creating sugars (foods) from carbon dioxide and water.

chloroplast     A tiny structure in the cells of green algae and green plants that contain chlorophyll and creates glucose through photosynthesis.

oxygen     A gas that makes up about 21 percent of the atmosphere. All animals and many microorganisms need oxygen to fuel their metabolism.

pigment     A material, like the natural colorings in skin, that alter the light reflected off of an object or transmitted through it. The overall color of a pigment typically depends on which wavelengths of visible light it absorbs and which ones it reflects. For example, a red pigment tends to reflect red wavelengths of light very well and typically absorbs other colors. Pigment also is the term for chemicals that manufacturers use to tint paint.

wavelength     The distance between one peak and the next in a series of waves, or the distance between one trough and the next. Visible light — which, like all electromagnetic radiation, travels in waves — includes wavelengths between about 380 nanometers (violet) and about 740 nanometers (red). Radiation with wavelengths shorter than visible light includes gamma rays, X-rays and ultraviolet light. Longer-wavelength radiation includes infrared light, microwaves and radio waves.


  • MS-LS1-1
  • MS-LS1-6
  • HS-LS1-5