Why is chlorophyll important for all biological life

Chlorophyll , the primary pigment used in photosynthesis, reflects green light and absorbs red and blue light most strongly. In plants, photosynthesis takes place in chloroplasts, which contain the chlorophyll.

Chloroplasts are surrounded by a double membrane and contain a third inner membrane, called the thylakoid membrane , that forms long folds within the organelle. In electron micrographs, thylakoid membranes look like stacks of coins, although the compartments they form are connected like a maze of chambers.

The green pigment chlorophyll is located within the thylakoid membrane, and the space between the thylakoid and the chloroplast membranes is called the stroma Figure 3, Figure 4. Chlorophyll A is the major pigment used in photosynthesis, but there are several types of chlorophyll and numerous other pigments that respond to light, including red, brown, and blue pigments.

These other pigments may help channel light energy to chlorophyll A or protect the cell from photo-damage. For example, the photosynthetic protists called dinoflagellates, which are responsible for the "red tides" that often prompt warnings against eating shellfish, contain a variety of light-sensitive pigments, including both chlorophyll and the red pigments responsible for their dramatic coloration. Figure 4: Diagram of a chloroplast inside a cell, showing thylakoid stacks Shown here is a chloroplast inside a cell, with the outer membrane OE and inner membrane IE labeled.

Other features of the cell include the nucleus N , mitochondrion M , and plasma membrane PM. At right and below are microscopic images of thylakoid stacks called grana. Note the relationship between the granal and stromal membranes.

Protein import into chloroplasts. Nature Reviews Molecular Cell Biology 5, doi Figure Detail. Photosynthesis consists of both light-dependent reactions and light-independent reactions.

In plants, the so-called "light" reactions occur within the chloroplast thylakoids, where the aforementioned chlorophyll pigments reside. When light energy reaches the pigment molecules, it energizes the electrons within them, and these electrons are shunted to an electron transport chain in the thylakoid membrane. Meanwhile, each chlorophyll molecule replaces its lost electron with an electron from water; this process essentially splits water molecules to produce oxygen Figure 5.

Figure 5: The light and dark reactions in the chloroplast The chloroplast is involved in both stages of photosynthesis. The light reactions take place in the thylakoid. There, water H 2 O is oxidized, and oxygen O 2 is released. The dark reactions then occur outside the thylakoid. The products of this reaction are sugar molecules and various other organic molecules necessary for cell function and metabolism.

Note that the dark reaction takes place in the stroma the aqueous fluid surrounding the stacks of thylakoids and in the cytoplasm. The thylakoids, intake of water H 2 O , and release of oxygen O 2 occur on the yellow side of the cell to indicate that these are involved in the light reactions. The carbon fixation reactions, which involve the intake of carbon dioxide CO 2 , NADPH, and ATP, and the production of sugars, fatty acids, and amino acids, occur on the blue side of the cell to indicate that these are dark reactions.

An arrow shows the movement of a water molecule from the outside to the thylakoid stack on the inside of the chloroplast. Another arrow shows light energy from the sun entering the chloroplast and reaching the thylakoid stack. An arrow shows the release of an oxygen molecule O 2 from the thylakoid stack to the outside of the chloroplast. Once the light reactions have occurred, the light-independent or "dark" reactions take place in the chloroplast stroma. During this process, also known as carbon fixation, energy from the ATP and NADPH molecules generated by the light reactions drives a chemical pathway that uses the carbon in carbon dioxide from the atmosphere to build a three-carbon sugar called glyceraldehydephosphate G3P.

Cells then use G3P to build a wide variety of other sugars such as glucose and organic molecules. Many of these interconversions occur outside the chloroplast, following the transport of G3P from the stroma. The products of these reactions are then transported to other parts of the cell, including the mitochondria, where they are broken down to make more energy carrier molecules to satisfy the metabolic demands of the cell.

In plants, some sugar molecules are stored as sucrose or starch. This page appears in the following eBook. Aa Aa Aa. Photosynthetic Cells. What Is Photosynthesis? Why Is it Important? Figure 2. Figure 3: Structure of a chloroplast. Figure 4: Diagram of a chloroplast inside a cell, showing thylakoid stacks. Shown here is a chloroplast inside a cell, with the outer membrane OE and inner membrane IE labeled. What Are the Steps of Photosynthesis?

Figure 5: The light and dark reactions in the chloroplast. The chloroplast is involved in both stages of photosynthesis. Photosynthetic cells contain chlorophyll and other light-sensitive pigments that capture solar energy.

In the presence of carbon dioxide, such cells are able to convert this solar energy into energy-rich organic molecules, such as glucose. The initiative is part of a broader But, it is a complex phenomenon, which involves a myriad of proteins.

The molecule Chl f, a If collected via satellite, In a first, a team has deciphered in detail at the protein level what makes them turn red as they ripen. At the heart of Science has not provided a good answer to this This new organic proxy not only provides And researchers Animals that eat plants or other animals are called heterotrophs.

Because food webs in every type of ecosystem, from terrestrial to marine, begin with photosynthesis, chlorophyll can be considered a foundation for all life on Earth. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.

The Rights Holder for media is the person or group credited. Tyson Brown, National Geographic Society. National Geographic Society. For information on user permissions, please read our Terms of Service. If you have questions about how to cite anything on our website in your project or classroom presentation, please contact your teacher. They will best know the preferred format.

When you reach out to them, you will need the page title, URL, and the date you accessed the resource. If a media asset is downloadable, a download button appears in the corner of the media viewer. If no button appears, you cannot download or save the media. Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website.

You cannot download interactives. Marine ecosystems contain a diverse array of living organisms and abiotic processes. From massive marine mammals like whales to the tiny krill that form the bottom of the food chain, all life in the ocean is interconnected. While the ocean seems vast and unending, it is, in fact, finite; as the climate continues to change, we are learning more about those limits.