Fats consist of a wide group of compounds that are generally soluble in organic solvents and largely insoluble in water. Chemically, fats are generally triesters of glycerol and fatty acids. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least In Chemistry, especially Biochemistry, a fatty acid is a Carboxylic acid often with a long unbranched Aliphatic tail ( chain) which Fats may be either solid or liquid at normal room temperature, depending on their structure and composition. A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Although the words "oils", "fats" and "lipids" are all used to refer to fats, "oils" is usually used to refer to fats that are liquids at normal room temperature, while "fats" is usually used to refer to fats that are solids at normal room temperature. An oil is a substance that is in a viscous Liquid state ( "oily") at ambient temperatures or slightly warmer and is Lipids are broadly defined as any fat- Soluble ( lipophilic) naturally-occurring Molecule, such as fats oils waxes cholesterol sterols fat-soluble "Lipids" is used to refer to both liquid and solid fats. The word "oil" is used for any substance that does not mix with water and has a greasy feel, such as petroleum (or crude oil) and heating oil, regardless of its chemical structure. Petroleum ( L petroleum, from Greek πετρέλαιον, lit Heating oil, or oil heat, also known in the United States as No ^[1]

Fats form a category of lipid, distinguished from other lipids by their chemical structure and physical properties. Lipids are broadly defined as any fat- Soluble ( lipophilic) naturally-occurring Molecule, such as fats oils waxes cholesterol sterols fat-soluble Chemical structure refers to Molecular geometry, Electronic structure and Crystal structure. This category of molecules is important for many forms of life, serving both structural and metabolic functions. They are an important part of the diet of most heterotrophs (including humans). This article is primarily about the human diet For a discussion of animal diets see List of feeding behaviours. A heterotrophs, or chemoorganotrophy ( Greek heterone = (another and trophe = nutrition is an Organism that requires Fats or lipids are broken down in the body by enzymes called lipases produced in the pancreas. A lipase is a Water-soluble Enzyme that Catalyzes the Hydrolysis of Ester bonds in water–insoluble Lipid

Examples of edible animal fats are lard (pig fat), fish oil, and butter or ghee. Lard is pig Fat in both its rendered and unrendered forms Lard was commonly used in many cuisines as a Cooking fat or Shortening Fish oil is Oil derived from the tissues of Oily fish. Fish oil is recommended for a healthy diet because it contains the Omega-3 Butter is a Dairy product made by churning fresh or fermented Cream or Milk. Ghee ( Hindi घी ghī, Urdu گھی ghī, Punjabi ਘਿਉ/گھیو ghiu, Kashmiri ग्याव/گیاو They are obtained from fats in the milk, meat and under the skin of the animal. Examples of edible plant fats are peanut, soya bean, sunflower, sesame, coconut, olive and vegetable oils. Margarine and vegetable shortening, which can be derived from the above oils, are used mainly for baking. Margarine (ˈmɑrdʒərɨn /ˈmɑrdʒəriːn/ or /ˈmɑrgəriːn/ as a generic term can indicate any of a wide range of Butter substitutes Shortening is a semisolid Fat used in food preparation especially baked goods and is so called because it promotes a "short" or crumbly texture (as in Shortbread These examples of fats can be categorized into saturated fats and unsaturated fats. Saturated fat is Fat that consists of Triglycerides containing only saturated Fatty acids Explanation Fat that occurs An unsaturated fat is a Fat or Fatty acid in which there are one or more Double bonds in the fatty acid chain

Chemical structure

A triglyceride molecule

There are many different kinds of fats, but each is a variation on the same chemical structure. (more properly known as, TAG or triacylglyceride) is Glyceride in which the Glycerol is Esterified with three Fatty acids It is the All fats consist of fatty acids (chains of carbon and hydrogen atoms, with a carboxylic acid group at one end) bonded to a backbone structure, often glycerol (a "backbone" of carbon, hydrogen, and oxygen). In Chemistry, especially Biochemistry, a fatty acid is a Carboxylic acid often with a long unbranched Aliphatic tail ( chain) which Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 Carboxylic acids are Organic acids characterized by the presence of a Carboxyl group, which has the formula -C(=OOH usually written -COOH or -CO2H Chemically, this is a triester of glycerol, an ester being the molecule formed from the reaction of the carboxylic acid and an organic alcohol. Esters are a class of Chemical compounds and Functional groups Esters consist of an inorganic or organic Acid in which at least As a simple visual illustration, if the kinks and angles of these chains were straightened out, the molecule would have the shape of a capital letter E. Molecular geometry or molecular structure is the three- Dimensional arrangement of the Atoms that constitute a Molecule. The fatty acids would each be a horizontal line; the glycerol "backbone" would be the vertical line that joins the horizontal lines. Fats therefore have "ester" bonds. A chemical bond is the physical process responsible for the attractive interactions between Atoms and Molecules and which confers stability to diatomic and polyatomic

The properties of any specific fat molecule depend on the particular fatty acids that constitute it. Different fatty acids are comprised of different numbers of carbon and hydrogen atoms. The carbon atoms, each bonded to two neighboring carbon atoms, form a zigzagging chain; the more carbon atoms there are in any fatty acid, the longer its chain will be. Fatty acids with long chains are more susceptible to intermolecular forces of attraction (in this case, van der Waals forces), raising its melting point. The Van der Waals equation is an Equation of state that can be derived from a special form of the potential between a pair of molecules (hard-sphere repulsion The melting point of a solid is the temperature range at which it changes state from solid to Liquid. Long chains also yield more energy per molecule when metabolized. In Physics and other Sciences energy (from the Greek grc ἐνέργεια - Energeia, "activity operation" from grc ἐνεργός

A fat's constituent fatty acids may also differ in the number of hydrogen atoms that are bonded to the chain of carbon atoms. Each carbon atom is typically bonded to two hydrogen atoms. When a fatty acid has this typical arrangement, it is called "saturated", because the carbon atoms are saturated with hydrogen; meaning they are bonded to as many hydrogens as possible. In other fats, a carbon atom may instead bond to only one other hydrogen atom, and have a double bond to a neighboring carbon atom. This results in an "unsaturated" fatty acid. More specifically, it would be a "monounsaturated" fatty acid, whereas, a "polyunsaturated" fatty acid would be a fatty acid with more than one double bond. Saturated and unsaturated fats differ in their energy content and melting point. Since an unsaturated fat contains fewer carbon-hydrogen bonds than a saturated fat with the same number of carbon atoms, unsaturated fats will yield slightly less energy during metabolism than saturated fats with the same number of carbon atoms. Saturated fats can stack themselves in a closely packed arrangement, so they can freeze easily and are typically solid at room temperature. But the rigid double bond in an unsaturated fat fundamentally changes the chemistry of the fat. There are two ways the double bond may be arranged: the isomer with both parts of the chain on the same side of the double bond (the cis-isomer), or the isomer with the parts of the chain on opposite sides of the double bond (the trans-isomer). Most trans-isomer fats (commonly called trans fats) are commercially produced rather than naturally occurring. Trans fat is the common name for a type of Unsaturated fat with trans - isomer Fatty acid (s The cis-isomer introduces a kink into the molecule that prevents the fats from stacking efficiently as in the case of fats with saturated chains. This decreases intermolecular forces between the fat molecules, making it more difficult for unsaturated cis-fats to freeze; they are typically liquid at room temperature. Trans fats may still stack like saturated fats, and are not as susceptible to metabolization as other fats. Trans fats and saturated fats significantly increase the risk of coronary heart disease. Coronary disease (or coronary heart disease) refers to the failure of Coronary circulation to supply adequate circulation to Cardiac muscle and surrounding ^[2]

Importance for living organisms

Vitamins A, D, E, and K are fat-soluble, meaning they can only be digested, absorbed, and transported in conjunction with fats. A vitamin is an Organic compound required as a Nutrient in tiny amounts by an Organism. Vitamin A refers to a family of similarly shaped molecules the Retinoids. Vitamin D is a group of fat-soluble Prohormones, the two major forms of which are vitamin D2 (or Ergocalciferol) and vitamin D3 (or See also Tocopherol, Tocotrienol Vitamin E is the collective name for a set of 8 related Tocopherols and Tocotrienols which are fat-soluble Vitamin K (K from "Koagulations-Vitamin" in German Danish Swedish and Norwegian denotes a group of Lipophilic, Hydrophobic Vitamins that Fats are also sources of essential fatty acids, an important dietary requirement. Essential fatty acids, or EFAs are Fatty acids that cannot be constructed within an organism from other components (generally all references are to humans by any known chemical

Fats play a vital role in maintaining healthy skin and hair, insulating body organs against shock, maintaining body temperature, and promoting healthy cell function. The skin is the outer covering of living tissue of an animal (or plant Hair is a keratinised protein filament that grows through the epidermis from follicles deep within the Dermis. They also serve as energy stores for the body. Fats are broken down in the body to release glycerol and free fatty acids. In Chemistry, especially Biochemistry, a fatty acid is a Carboxylic acid often with a long unbranched Aliphatic tail ( chain) which The glycerol can be converted to glucose by the liver and thus used as a source of energy. Glucose (Glc a Monosaccharide (or simple Sugar) also known as grape sugar, is an important Carbohydrate in Biology.

The fat content of a food can be analyzed by extraction. The exact method varies on what type of fat to be analyzed—for example, polyunsaturated and monounsaturated fats are tested quite differently.

Fat also serves as a useful buffer towards a host of diseases. When a particular substance, whether chemical or biotic—reaches unsafe levels in the bloodstream, the body can effectively dilute—or at least maintain equilibrium of—the offending substances by storing it in new fat tissue. This helps to protect vital organs, until such time as the offending substances can be metabolized and/or removed from the body by such means as excretion, urination, accidental or intentional bloodletting, sebum excretion, and hair growth. Excretion is the process of eliminating waste products of Metabolism and other non-useful materials Urination, also known as micturition, voiding, and more rarely emiction, is the process of disposing Urine from the Urinary bladder Bloodletting (or blood-letting, in modern medicine referred to as phlebotomy) was a tremendously popular medical practice from antiquity up to the late The sebaceous glands are Glands found in the Skin of Mammals Locations and morphology A branched type of Acinar gland, these Hair is a keratinised protein filament that grows through the epidermis from follicles deep within the Dermis.

While it is nearly impossible to remove fat completely from the diet, it would be wrong to do so. Some fatty acids are essential nutrients, meaning that they can't be produced in the body from other compounds and need to be consumed in small amounts. All other fats required by the body are non-essential and can be produced in the body from other compounds.

Adipose tissue

The obese mouse on the left has large stores of adipose tissue. Obesity is a condition in which excess Body fat has accumulated to such an extent that health may be negatively affected A mouse (plural mice) is a small Animal that belongs to one For comparison, a mouse with a normal amount of adipose tissue is shown on the right.

Main article: Adipose tissue

In animals, adipose, or fatty tissue is the body's means of storing metabolic energy over extended periods of time. "Adipose" redirects here For the Doctor Who monster see " Partners in Crime " "Adipose" redirects here For the Doctor Who monster see " Partners in Crime " Depending on current physiological conditions, adipocytes store fat derived from the diet and liver metabolism or degrades stored fat to supply fatty acids and glycerol to the circulation. Physiology (from Greek grc φύσις physis, "nature origin" and grc -λογία -logia) is the study of the mechanical physical Adipocytes are the cells that primarily compose Adipose tissue, specialized in storing energy as Fat. Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. In Chemistry, especially Biochemistry, a fatty acid is a Carboxylic acid often with a long unbranched Aliphatic tail ( chain) which This is an article about the rock music band "Circulatory System" These metabolic activities are regulated by several hormones (i. e. , insulin, glucagon and epinephrine). Insulin is a Hormone with intensive effects on both metabolism and several other body systems (eg vascular compliance Glucagon is an important Hormone involved in Carbohydrate metabolism. The location of the tissue determines its metabolic profile: "Visceral fat" is located within the abdominal wall (i. e. , beneath the wall of abdominal muscle) whereas "subcutaneous fat" is located beneath the skin (and includes fat that is located in the abdominal area beneath the skin but above the abdominal muscle wall). It was briefly thought that visceral fat produced a hormone involved in insulin resistance, but this has been disproved by clinical tests (see, resistin, a hormone, ultimately misnamed, which is produced by adipose tissue and does cause insulin resistance in mice but not in humans). Insulin resistance is the condition in which normal amounts of Insulin are inadequate to produce a normal Insulin response from Fat, Muscle Resistin is a Hormone secreted by Adipose tissue. It is also known as " Serine / Cysteine -rich Adipocyte -Specific Secretory

See also

References

• Donatelle, Rebecca J. (2005). Health, The Basics, 6th ed, San Francisco: Pearson Education, Inc. The City and County of San Francisco is the fourth most populous city  

External links