Disaccharides are formed as a result of condensation reaction between two monosaccharides (hexoses) with loss of water molecule.
Lecture 9. Chemical competition evening. The plan of the evening dedicated for D.I.Mendeleyev`s life and scientific work.
The chemical composition of the cell is divided into organic and inorganic substances.
Organic: proteins, fats and carbohydrates. Inorganic: water, mineral salts.
Functions of organic substances.
Proteins:
- participate in gas exchange between lungs and organs,
- muscle contraction,
- perform a protective function
Fats act as a reserve source of energy.
Carbohydrates are the main source of energy. Performs the function of construction.
The structure of organic substances:
Proteins
These are polymers whose monomers are amino acids. They are mainly composed of carbon, hydrogen, oxygen and nitrogen. The protein molecule can have 4 levels of structural organization (primary, secondary, tertiary and Quaternary structures).
Fats
Fats (lipids) can be simple and complex. Molecules of simple lipids are composed of trivalent alcohol glycerol and three of fatty acid residues. Complex lipids are compounds of simple lipids with proteins and carbohydrates.
Carbohydrates
These are mono-and polymers, which include carbon, hydrogen and oxygen in a ratio of 1:2:1.
Inorganic mineral substance of the cell.
Potassium is involved in the regulation of muscle activity.
Nitride moves substances in the body, takes part in the process of transmission of nerve impulses.
Calcium is part of the bones.
Water is involved in all processes that occur in the body.
Magnesium transmits nerve impulses and is involved in muscle activity.
Plant and animal cells contain inorganic and organic substances. To inorganic include water and minerals. Organic substances include proteins, fats, carbohydrates, nucleic acids.
Inorganic substance
Water is the compound that the living cell contains the most. Water is about 70% of the cell mass. Most intracellular reactions occur in the aqueous medium. The water in the cell is free and bound.
The value of water for the life of the cell is determined by its structure and properties. The water content in the cells may be different. 95% of the water is in the cell in a free state. It is essential as a solvent for organic and inorganic substances. All biochemical reactions in the cell are with the participation of water. Water is used to remove various substances from the cell. Water has high thermal conductivity and prevents sharp temperature fluctuations. 5% of water is in a bound state, forming unstable compounds with proteins.
Mineral substances in the cell may be in a dissociated state or in combination with organic substances.
Chemical elements that are involved in metabolic processes and have biological activity, called biogenic.
The cytoplasm contains about 70% oxygen, 18% carbon, 10% hydrogen, calcium, nitrogen, potassium, phosphorus, magnesium, sulfur, chlorine, sodium, aluminum, iron. These elements make up 99.99% of the cell composition and they are called macronutrients. For example, calcium and phosphorus are part of bones. Iron-part of hemoglobin.
Manganese, boron, copper, zinc, iodine, cobalt - trace elements. They make up a thousandths of a percent of the cell mass. Microelements are needed for the formation of hormones, enzymes, vitamins. They affect the metabolic processes in the body. For example, iodine is part of the thyroid hormone, cobalt is part of vitamin B12.
Gold, mercury, radium, etc. ultramicroelements - are millionths of a percent of the composition of cells.
Lack or excess of mineral salts disrupts the body's life.
Organic matter
Oxygen, hydrogen, carbon, nitrogen are part of organic substances. Organic compounds are large molecules called polymers. Polymers consist of many repeating units (monomers). Organic polymeric compounds include carbohydrates, fats, proteins, nucleic acids, ATP.
Carbohydrates
Carbohydrates consist of carbon, hydrogen, oxygen.
Monomers of carbohydrates are monosaccharides. Carbohydrates are divided into monosaccharides, disaccharides and polysaccharides.
Monosaccharides are simple sugars with the formula (CH2O)n , where n is any integer from three to seven. Depending on the number of carbon family atoms in the molecule are distinguished triose (3C), tetrose (4C), pentoses (5C), hexoses (6C), heptose (7C).
C3h6o3 trioses - for example, glyceraldehyde and dihydroxyacetone - play the role of intermediates in the process of respiration, participate in photosynthesis. Tetrose С4Н8О4 occur in bacteria. Pentose C5N10O5 - for example ribose-is part of RNA, deoxyribose is part of DNA. Hexose - is c6h12o6 e.g. glucose, fructose, galactose. Glucose is a source of energy for the cell. Together with fructose and galactose glucose can participate in the formation of disaccharides.
Disaccharides are formed as a result of condensation reaction between two monosaccharides (hexoses) with loss of water molecule.
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