Along with proteins, carbohydrates and nucleic acids of great importance to all living organisms are also lipids.This organic compounds with important biological functions.Therefore, constant replenishment of the body is essential for normal life.What do they represent in terms of chemistry and some lipids in the cell perform the functions we learn from this article.
Lipids: general concept
If you give a general characterization of the compounds in question, it can be said that the organic substance of the cell lipids - are complex fat-like molecules that comprise its membership of hydrophilic and hydrophobic part.
Simply put, all the fats of vegetable and animal origin, waxes, cholesterol, many hormones, terpenes - all lipids.Just this term refer to the totality of the properties of these compounds.All of them - are insoluble in water but soluble in nonpolar organic compound materials.Oily to the touch.
lipid composition in terms of chemistry rather complicated and depends on what the particular compound in question.Therefore, this issue will consider separately.
Classification
Distribute all lipids in the group can be on different grounds.One of the most common classification is based on the ability of molecules to hydrolysis.According to this characteristic distinguish two large groups of organic fat.
- saponified - those that are subjected to hydrolysis and decompose into its constituent parts.Examples: waxes, phospholipids, sterol esters, neutral fats.
- Unsaponifiable - those that do not undergo hydrolysis.These include the terpenes, sterols, fat-soluble vitamins (A, D, E, K), cholesterol, estradiol, testosterone, and other.
There is another feature of the classification of the substances - the number of members of the components.Thus, the release:
- two-component, or simple (fats and waxes of plants);
- multicomponent, or complex (phospholipids, glycolipids, and other ornitinolipidy).
general lipids in the cell function as very important, since they are direct or indirect participants in all vital processes.Therefore, the diversity of their very high.
lipid composition
From a chemical point of view of a molecule like substances composed of two main components:
- hydrophobic component;
- hydrophilic.
Since lipids very much, and examples of both parts as much.To understand the chemical composition of the compounds present examples.
What compounds are hydrophobic components of the lipid molecules?
- higher fatty acids (IVH).
- higher alcohols.
- Higher aldehydes.
hydrophilic molecular components of the following:
- glycerol;
- aminodioly;
- carbohydrates;
- phosphoric and sulfuric acid;
- amino alcohols;
- amino acids.
Various combinations of these components, hold down next to each other by ionic, covalent interactions, the forces of electrostatic attraction and hydrogen bonds, forming the diversity of oily water insoluble compounds, collectively known as lipids.
Structure and properties of lipids
properties are explained by their chemical structure.So, if in the highest part of the unsaturated carboxylic acid and glycerin, the fat will be the characteristics of acid and a trihydric alcohol.If a part of the aldehyde, then the reaction will be those that are characteristic of the keto group.
Therefore, the relationship of properties and chemical structure of the molecule is quite obvious.The only common to all kinds of fats characteristics - is:
- solubility in benzene, hexane, chloroform and other non-polar solvents;
- oiliness or greasiness to the touch.
Converting cell
Those lipids which perform a function in the body of reserve nutrients, energy sources, are neutral fats.According to the classification of the substances it will be a mixture of triacylglycerols.The hydrophobic, water-insoluble, non-polar compounds is the formation of glycerol and three molecules of higher carboxylic acids.
These lipids are processed in the cells of living organisms.What kind of transformation?It is a process of hydrolysis with special enzymes, called lipases.As a result, complete digestion produced a molecule of glycerol and fatty acids.They then enter the bloodstream into cells and subjected to further processing - the synthesis of lipids in a cell of a different structure.
There are a number of higher fatty acids, which are essential for a person as yourself in the cells are formed.It:
- oleic;
- linoleic;
- linolenic.
to maintain normal lipid levels should eat foods rich in these acids: meat, fish, eggs, poultry meat, herbs, nuts, cheese and others, cereals.
role of lipids in the cell
What is the significance of fat for the body?The lipids in the cell function as:
- redundant and energy;
- structural;
- signal;
- protective.
Each of them is very important to maintain the normal life of every living being.
Of particular importance are those that formed unsaturated acids, as they are indispensable.They are involved in the formation of specific molecules prostaglandins, which in turn, are regulators of many processes.Also, it is the properties of this group of lipids to neutralize cholesterol and prevent atherosclerosis.
Stand-energy and structure function
triacylglycerol or neutral fats - are the main source of energy for many internal organs (liver, kidneys, muscles).Upon cleavage of 1 gram of lipids released 9.3 kcal of heat, which is significantly higher than the corresponding figure in the decay of carbohydrates and proteins.
Therefore, at the time of fasting for the body fat - is a source of vitality and energy.Lipids in the cell perform structural functions as part of the cell membranes.This molecules such as:
- glycolipids;
- phospholipids;
- cholesterol.
Such lipid, phosphatidylcholine is a must as the structural unit of the liver cells.Therefore, the backup function of fat - a storage of them in separate parts of the body.Energy - this splitting if necessary with the release of energy.A block is that it is constructed from lipids some parts of cells and tissues.
warning and protective
Signaling function of lipids is that many of them are carriers of the important signals from the cell and inside it.These are fats like:
- phosphatidylinositol;
- eicosanoids;
- glycolipids.
They bind to hormones and provide quick transmission of information in and out of the cell.Also, fats provide the regulation of many functions that are carried out by the cells.
protective role of lipids is that the mass of fat and provides thermal insulation and mechanical protection of the internal organs from damage.The man (women) the main concentration of fat during pregnancy - abdomen.What it is also a tool for the protection of the fetus against bumps, collisions and other influences.
Furthermore, phospholipids play an important role in activating the proteins and hormones working in blood coagulation.Since this process is also a security device body, the function of fat in this case is the same.
