please give me a paragraph of photosynthesis in 2000 words
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Answer:
Photosynthesis is the process used by plants, algae and certain bacteria to harness energy from sunlight and turn it into chemical energy. Here, we describe the general principles of photosynthesis and highlight how scientists are studying this natural process to help develop clean fuels and sources of renewable energy.
Types of photosynthesis
There are two types of photosynthetic processes: oxygenic photosynthesis and anoxygenic photosynthesis. The general principles of anoxygenic and oxygenic photosynthesis are very similar, but oxygenic photosynthesis is the most common and is seen in plants, algae and cyanobacteria.
During oxygenic photosynthesis, light energy transfers electrons from water (H2O) to carbon dioxide (CO2), to produce carbohydrates. In this transfer, the CO2 is "reduced," or receives electrons, and the water becomes "oxidized," or loses electrons. Ultimately, oxygen is produced along with carbohydrates.
Oxygenic photosynthesis functions as a counterbalance to respiration by taking in the carbon dioxide produced by all breathing organisms and reintroducing oxygen to the atmosphere.
On the other hand, anoxygenic photosynthesis uses electron donors other than water. The process typically occurs in bacteria such as purple bacteria and green sulfur bacteria, which are primarily found in various aquatic habitats.
"Anoxygenic photosynthesis does not produce oxygen — hence the name," said David Baum, professor of botany at the University of Wisconsin-Madison. "What is produced depends on the electron donor. For example, many bacteria use the bad-eggs-smelling gas hydrogen sulfide, producing solid sulfur as a byproduct."
Though both types of photosynthesis are complex, multistep affairs, the overall process can be neatly summarized as a chemical equation.
Oxygenic photosynthesis is written as follows:
6CO2 + 12H2O + Light Energy → C6H12O6 + 6O2 + 6H2O
Here, six molecules of carbon dioxide (CO2) combine with 12 molecules of water (H2O) using light energy. The end result is the formation of a single carbohydrate molecule (C6H12O6, or glucose) along with six molecules each of breathable oxygen and water.
Similarly, the various anoxygenic photosynthesis reactions can be represented as a single generalized formula:
CO2 + 2H2A + Light Energy → [CH2O] + 2A + H2O
The letter A in the equation is a variable and H2A represents the potential electron donor. For example, A may represent sulfur in the electron donor hydrogen sulfide (H2S), explained Govindjee and John Whitmarsh, plant biologists at the University of Illinois at Urbana-Champaign, in the book "Concepts in Photobiology: Photosynthesis and Photomorphogenesis" (Narosa Publishers and Kluwer Academic, 1999).
may be attachment helps u
Explanation:
Answer:
Explanation:
Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
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WRITTEN BY: Hans LambersJames Alan Bassham
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overview of photosynthesis
overview of photosynthesis
The location, importance, and mechanisms of photosynthesis. Study the roles of chloroplasts, chlorophyll, grana, thylakoid membranes, and stroma in photosynthesis.
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Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
photosynthesis
photosynthesis
Diagram of photosynthesis showing how water, light, and carbon dioxide are absorbed by a plant to produce oxygen, sugars, and more carbon dioxide.
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Photosynthesis
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KEY PEOPLE
Joseph Priestley
Melvin Calvin
Jan Ingenhousz
Jean Senebier
Robert Huber
Johann Deisenhofer
Nicolas-Théodore de Saussure
Hartmut Michel
Robert Hill
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Plant
Life
Chloroplast
Blue-green algae
Elysia chlorotica
Chlorophyll
Photolysis
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Living things
It would be impossible to overestimate the importance of photosynthesis in the maintenance of life on Earth. If photosynthesis ceased, there would soon be little food or other organic matter on Earth. Most organisms would disappear, and in time Earth’s atmosphere would become nearly devoid of gaseous oxygen. The only organisms able to exist under such conditions would be the chemosynthetic bacteria, which can utilize the chemical energy of certain inorganic compounds and thus are not dependent on the conversion of light energy.