Biochemistry

7.2 FORMATION OF CARBOHYDRATES IN PHOTOSYNTHESIS Carbohydrates in nature plays an extremely important role. They are the products of CO 2 assimilation by plants .Organic matter arises from inorganic in the green parts of plants under the action of red and blue-violet rays of the solar spectrum. This process is called photosynthesis. Photosynthesis is a set of processes during which solar energy is stored in the form of chemical bonds of organic compounds. Photosynthesis in nature occurs in special organelles of plant cells - chloroplasts. They contain several types of colored pigments - chlorophylls , which are associated with proteins and lipids. In their structure, chlorophylls resemble hemoglobin heme, but it does not contain iron, but magnesium. A great contribution to the study of photosynthesis was made by the Russian scientist K. A. Timiryazev. He proved that the green color of plants that arose during evolution can be considered as a useful device that contributes to the best accumulation of solar energy in the conditions of our planet. Solar energy is absorbed by chlorophyll and then used in the decomposition of water (photolyz). In tliis released oxygen and an activated hydrogen is transferred to phosphoglyceric acid appearing in the absorption plant CO 2 ; then glucose, starch and other carbohydrates are formed from it. (HCHOX Figure 7.2 - Photosynthesis layout The release of oxygen during photosynthesis is an important source of its formation in the atmosphere (Fig. 7.2). Thus, green plants play a crucial biochemical role - they bind carbon dioxide and release oxygen. In photosynthesis, three series of reactions are distinguished: 154