Photosynthesis is essential for almost everything living, and it is the main source of oxygen in the atmosphere.
Photosynthesis surrounds us everywhere. It happens under our feet, above our heads, and in the sun-lit areas of the aquatic environment. But what is photosynthesis? Why is it so important? And when did it appear? The answers to these and other questions will be found below.
What is photosynthesis?
Photosynthesis is a process in which carbohydrate molecules are synthesized. It is used by plants, algae and some bacteria to convert sunlight, water and carbon dioxide into oxygen and energy in the form of sugar. It is probably the most important biochemical process on the planet.
In fact, it takes the carbon dioxide emitted by all the breathing organisms and restores it to the atmosphere in the form of oxygen.
The speed of photosynthesis is influenced by the intensity of the lighting, the concentration of carbon dioxide, the flow of water, the temperature and the availability of minerals, the process taking place entirely in chloroplastics, and it is the chlorophyll contained in chloroplastics that gives the photosynthesis parts of the plant a green color.
Photosynthesis is also important in other parts of the biosphere: both marine and terrestrial plants extract carbon dioxide from the atmosphere and some of it is deposited back as calcium carbonate shells or stored in soil as organic matter.
Without photosynthesis, the carbon cycle could not have taken place, and we would soon have run out of food, and with time, the atmosphere would have lost almost all of the gaseous oxygen, and most organisms would have disappeared.
How's the photosynthesis going?
Plants need light energy, carbon dioxide, water and nutrients from both the surrounding atmosphere and the soil.
Plants absorb sunlight through two top layers of leaves
Right under the cuticula and epidermis are the palissad cells of mesophyll, these specialized cells have a vertical, outstretched shape and are located close to each other to maximize light absorption.
Below the palesad mesophyll cells is a sponge mesophyllian tissue that is not well packed for effective gas exchange. When the gases move inside and out of these cells, they dissolve into a thin layer of water covering the cell.
Inside the palalysed cells of mesophiles are chloroplastics, many chloroplastics, and they contain chlorophyll, molecules that do not absorb the green waves of white light; instead, they reflect it back, giving plants a green color.
There's magic going on inside of the chloropolst. There's a light-dependent reaction in which the energy of the light waves is absorbed and stored in the energy-intensive ATF molecules.
Then, in a light independent reaction, the ATF is used to produce glucose, an energy source; water is oxidized, carbon dioxide is restored and oxygen is released into the atmosphere.
Oxygen is released through the stomach in the leaves, the microscopic pores that open to inject carbon dioxide and release oxygen.
What's the photosynthesis equation?
Photosynthetic organisms form the basis of the food chain.
Carbon dioxide + water = glucose + oxygen
In addition to light energy, carbon dioxide and water, plants need nutrients that they derive from the soil; these nutrients are released again, or processed when plant tissues die and decompose in the soil.
Oxygen in the form of gas molecules is a by-product of photosynthesis, but it is responsible for the oxygen content in the air that sustains our lives, and plants also release energy and water into the atmosphere in the process of breathing.
6CO2 + 6H2O * C6H12O6 + 6O2
The balanced equation goes a little further, six carbon dioxide molecules and six water molecules and six oxygen molecules using the light energy captured by chlorophyll.
Photosynthesis and the food chain
During photosynthesis, energy passes through the system, and you can think of photosynthesis as a system of energy flow that tracks the path of solar energy through the ecosystem. This energy is stored by primary producers, photosynthetic organisms. When these organisms are eaten and digested by primary consumers, chemical energy is released that is used to launch new biochemical reactions.
At each level of energy conversion throughout the food chain, part of the energy is lost as heat; moreover, much of the energy entering each organism is used in breathing to maintain the body ' s vitality; this energy is not stored for use by other organisms above the food chain.
When did the photosynthesis start?
The evolution of photosynthesis has had enormous consequences for the Earth, as the organic matter of photosynthetic life was buried in the earth's thickness, carbon was removed from the atmosphere, allowing oxygen to accumulate.
Evidence shows that photosynthetic organisms existed about 3.2 to 3.5 billion years ago as stromatolites. Stromatoliths are laminated microbial structures, usually formed by cyanobacteria and algae, and are the oldest known fossils, and thus the earliest evidence of life on Earth.
When this early oxygen spread into the upper atmosphere, solar radiation turned oxygen molecules into ozone, creating the ozone layer of the stratosphere, and, of course, since the ozone layer absorbs most of the solar ultraviolet radiation, it plays an important role in protecting human health, so it is unlikely that life would flourish without this shield.