About the Players
Photosynthesis is performed by chloroplasts, a highly specialized organelle found concentrated in leaves of plants. Within the chloroplasts are flattened disks known as thylakoids. A stack of thylakoid is called a granum. Multiple grana are found within the stroma (aqueous fluid in chloroplasts). Although photosynthesis is found to have occurred in the stroma, the majority of photosynthetic activity occurs on the thylakoid membrane, which contains the integral and peripheral membrane protein complexes needed to harvest light energy
In plants, leaves are considered the photosynthetic organs. Regardless of leaf shapes, they are highly concentrated in chloroplasts and are designed to maximize sunlight exposure and decreases distances that crucial gases must travel to reach the chloroplasts. They are also coated with a water-resistant, waxy cuticle to discourage excessive absorption of light and evaporation of water |
Within the chloroplasts of most plants are chlorophyll molecules. They are largely responsible for absorbing light energy and commencing photosynthesis. Its ability to transport light energy is thanks to the many alternating double and single bonds in its chemical structure, as well as its central magnesium atom. However, plants also contain other pigment molecules responsible for absorbing lights including carotenes and xanthophylls.
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