The glucides , along with lipids , protides , and nucleic acids , are one of the organic own immediate early living beings. In plants they are formed directly in photosynthesis , and it is the main organic component of these, much more abundant than in animals.
The main functions are two:
- It funció n reserve energy. The glucose is the most important carbohydrate because it is the main source of energy used by living things. The starch in plants, the glycogen in animals, etc., are ways to store thousands of glucoses.
- Structural function. It highlights the importance of the β bond, which prevents the degradation of these molecules and makes some organisms can remain hundreds of years, in the case of trees, maintaining structures up to 100 meters high. Among the carbohydrates with structural function we can mention: cellulose in plants, chitin in the cell wall of fungi and exoskele of arthropods, ribose and deoxyribose in the nucleic acids of all living beings, peptidoglycans in the wall cell bacteria, chondroitinin bones and cartilage, etc.
In addition, some carbohydrates have other specific functions, such as antibiotic (streptomycin), vitamin (vitamin C), anticoagulant (heparin), hormonal (gonadotropic hormones ), enzymatic (together with proteins they form ribonucleases) and immunological (membrane glycoproteins constitute antigens and, on the other hand, immunoglobulins or antibodies are partly made up of carbohydrates). Ribulose-1,5-bisphosphate is essential in the Calvin cycle, fixing CO2 in photosynthesis. Some carbohydrates bind to lipids or proteins of the cell membrane to form glycolipids and glycoproteins with signaling function, to be able to recognize hormones, antibodies, etc.