Process for the production of high-energy biomolecules with the help of light energy. Responsible for this are the chloroplasts (organ cells), in which the chlorophyll (leaf green) is located. By dyes such as chlorophyll, carotenoids and flavonoids in Scroll or other green parts of plants, solar radiation is used as an energy source to make carbohydrate compounds. It will carbon dioxide from the air and water to the carbohydrates glucose and fructose transformed while elemental oxygen is released. The absorption of solar energy by plants binds around 150 billion tonnes of carbon dioxide annually on Earth and releases 400 billion tonnes of oxygen.
In contrast to the assimilation is the reverse process of dissimilation or respiration (Breathing), in which sugar and oxygen are released into carbon dioxide and water releasing energy. In a cycle of 200 years each, the entire carbon dioxide in the atmosphere is bound in a biochemical cycle in the carbon compounds of plants, fungi and animals, in order to decompose through microorganisms to be released again as gas. From the primary carbohydrates formed by photosynthesis glucose and fructose and their storage form Strength and by the roots absorbed nutrient salts and trace elements All substances necessary for the plant life process are derived (assimilates, phytochemicals). Nutrient transport and water transport are separated in the plant.
The active transport of sugar from the Scroll by the Xylem the plant takes place in the transport form of sucrose through the phloem. This forms with the xylem the bipartite Leitgewebe. The xylem causes the passive transport of the water with the transpiration suction from the roots to the stomata of the leaves. Excess sugar is stored by the phloem in the berries, the trunk and the roots. In the berries, the water influx is blocked after reaching the full berry size to prevent bursting of the berry due to the strong osmotic effect of sugar. Important factors for optimal photosynthesis and sugar production are sufficient sunlight, warm temperatures (ideal for leaves are 15 to 30 ° C), a regulated water balance with a balanced ratio between water discharge and Water storage capacity in the ground, as well as a sufficient humidity (optimal are 60 to 70%).
Important nutrient are for the plants boron. iron. magnesium. sulfur and nitrogen, These are essential for the functioning of chlorophyll, which absorbs and converts the sun's energy so that photosynthesis can be initiated. The carbon dioxide is absorbed by small closeable pores (stomata) in the epidermis of the leaf undersides. These pores also release the oxygen and water vapor produced during photosynthesis. The biochemical process of photosynthesis is, so to speak, the first step in winemaking.
The yeasts convert the plant-produced sugar during fermentation into alcohol and carbon dioxide. Ultimately, the cycle in humans closes by the wine consumption, whereby the alcohol is burned in the metabolism and is converted back into water, energy and carbon dioxide. The maximization of the photosynthesis performance is central goal of many viticulture measures (see under foliage care ), since this directly determines the amount of sugar storage in the grapes. at heat stress (above 40 ° C) and dryness, photosynthesis is stopped. See also below respiration, the equivalent of photosynthesis, so to speak.
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