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Plants.
Plants ~ Life.
The importance of plants for this planet.
Show them ...
more
Plants.
Plants ~ Life.
The importance of plants for this planet.
Show them some care and respect.
Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, ferns, mosses, and green algae.
The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies.
Green plants, sometimes called Viridiplantae, obtain most of their energy from sunlight via a process called photosynthesis.
Photosynthesis (from the Greek φώτο- [photo-], "light," and σύνθεσις [synthesis], "putting together", "composition") is a process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight.
Photosynthesis occurs in plants, algae, and many species of Bacteria, but not in Archaea. Photosynthetic organisms are called photoautotrophs, since they can create their own food.
In plants, algae and cyanobacteria photosynthesis uses carbon dioxide and water, releasing oxygen as a waste product. Photosynthesis is vital for life on Earth.
As well as maintaining the normal level of oxygen in the atmosphere, nearly all life either depends on it directly as a source of energy, or indirectly as the ultimate source of the energy in their food.
The amount of energy trapped by photosynthesis is immense, approximately 100 terawatts, which is about six times larger than the power consumption of human civilization.
As well as energy, photosynthesis is also the source of the carbon in all the organic compounds within organisms' bodies. In all, photosynthetic organisms convert around 100,000,000,000 tonnes of carbon into biomass per year.
Although photosynthesis can happen in different ways in different species, some features are always the same. For example, the process always begins when energy from light is absorbed by proteins called photosynthetic reaction centers that contain chlorophylls. In plants, these proteins are held inside organelles called chloroplasts, while in bacteria they are embedded in the plasma membrane. Some of the light energy gathered by chlorophylls is stored in the form of adenosine triphosphate (ATP).
Photosynthesis changes the energy from the sun into chemical energy and splits water to liberate O2 and fixes CO2 into sugar.
The general equation for photosynthesis is therefore :
2n CO2 + 2n H2O + photons → 2(CH2O)n + n O2 + 2n A
Carbon dioxide + electron donor + light energy → carbohydrate + oxygen + oxidized electron donor
Important notice ! The all text is in video, i couldn' t save it all because it's too long, and You Tube couldn' t save it all.
Produced by
Ivan Ismailov
Rijeka, Croatia, Europe.
In Rijeka
17.04.2010.
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