Tags: What Questions Do You Need To Ask Before Writing An Academic EssayMla Heading For EssayThe Complete Writing A Great Research Paper SeriesEssay On TeensCritical Thinking S Nursing StudentsCustom Papers Essays Articles ConceptSuccession Planning For Small Business
In the Calvin cycle, atmospheric carbon dioxide is incorporated into already existing organic carbon compounds, such as ribulose bisphosphate (Ru BP).Using the ATP and NADPH produced by the light-dependent reactions, the resulting compounds are then reduced and removed to form further carbohydrates, such as glucose.
However, not all organisms use carbon dioxide as a source of carbon atoms to carry out photosynthesis; photoheterotrophs use organic compounds, rather than carbon dioxide, as a source of carbon.
In plants, algae, and cyanobacteria, photosynthesis releases oxygen.
In plants, these proteins are held inside organelles called chloroplasts, which are most abundant in leaf cells, while in bacteria they are embedded in the plasma membrane.
In these light-dependent reactions, some energy is used to strip electrons from suitable substances, such as water, producing oxygen gas.
The cells in the interior tissues of a leaf, called the mesophyll, can contain between 450,000 and 800,000 chloroplasts for every square millimeter of leaf.
The surface of the leaf is coated with a water-resistant waxy cuticle that protects the leaf from excessive evaporation of water and decreases the absorption of ultraviolet or blue light to reduce heating.
Most organisms that utilize oxygenic photosynthesis use visible light for the light-dependent reactions, although at least three use shortwave infrared or, more specifically, far-red radiation. The green part of the light spectrum is not absorbed but is reflected which is the reason that most plants have a green color.
Some organisms employ even more radical variants of photosynthesis. Besides chlorophyll, plants also use pigments such as carotenes and xanthophylls.
This produces a proton gradient more directly, which is then converted to chemical energy. In such proteins, the pigments are arranged to work together.
The process does not involve carbon dioxide fixation and does not release oxygen, and seems to have evolved separately from the more common types of photosynthesis. Such a combination of proteins is also called a light-harvesting complex.