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Renin Angiotensin Mechanism.

Physical Properties of Carbohydrates.

  Definition: Carbohydrates are hydrates of carbon, which on hydrolysis produce polyhydroxy aldehydes or polyhydroxy ketones . OR Carbohydrates are the derivatives of the polyhydroxy aldehydes or ketones or the products derived from them. Physical Properties of Carbohydrates: Asymmetric carbon atom A carbon atom to which four different atoms or groups of atoms are attached is said to be an asymmetric carbon atom. Many biochemicals contain two or more asymmetric carbon atoms. The presence of asymmetric carbon atom allows formation of isomers.  The compounds which have the same structural formula, but differ only in spatial configuration are called stereo-isomers or geometric isomers.  More the number of asymmetric carbon atoms, more are the number of isomers;  e.g. glucose with four asymmetric carbon atoms has 2"= 2 = 16 isomers ; n indicates the number of asymmetric carbon atoms. If the molecule contains one double bond with two different atoms or groups of atoms lin...

Biological Role of Carbohydrates.

  Definition: Carbohydrates are hydrates of carbon, which on hydrolysis produce polyhydroxy aldehydes or polyhydroxy ketones. Biological Role of Carbohydrates: Carbohydrates are the chief energy source in many animals; they are an instant source of energy.  Glucose is broken down by glycolysis/ krebs cycle to yield ATP.   Glucose is the source of storage of energy. It is stored as glycogen in animals and starch in plants.   Stored carbohydrates act as an energy source instead of proteins.   Carbohydrates are intermediates in biosynthesis of fats and proteins.   Carbohydrates aid in regulation of nerve tissue and are the energy source for the brain.   Carbohydrates get associated with lipids and proteins to form surface antigens, receptor molecules, vitamins and antibiotics.   They form structural and protective components, like in the cell wall of plants and microorganisms.   In animals they are an important...

Elimination: Introduction to Biotransformation.

  Elimination is the major process for removal of drugs from the body and termination of the drug action . It causes irreversible loss of the drug from the body . Eliminations occur two process: Biotransformation (metabolism) Excretion . Biotransformation: It is defined as the conversion of a chemical form of drug into another form using biological machinery . The products of biotransformation may vary, Some may retain activity. Some effectless. Some are even more effective . Xenobiotics: Any foregin chemical that is not a nutrient to the body and enters the body by ingestion, inhalation and absorption is called a xenobiotic . Organs of Biotransformation: Major site for biotransformation of xenobiotics is “Liver”. Other organs where biotransformation takes place are as follows, (Descending order of extent), Liver Lungs  Kidneys Intestine Placenta Skin. Other organs are brain, muscles, spleen etc. Drug metabolizing Enzymes: The enzymes that cause biotransformation of the xenob...

Carbohydrates Definition and Classification.

  Definition: Carbohydrates are hydrates of carbon, which on hydrolysis produce polyhydroxy aldehydes or polyhydroxy ketones. Introduction: Carbohydrates are products of plant origin and are a part of an extremely large group of naturally occurring organic compounds.  e.g.  Sugar Cane, Starch  Carbohydrates are a good source of energy. Carbohydrates are also known as saccharides , the word saccharide comes from the Greek word saccharon which means sugar. Classification of Carbohydrates: Carbohydrates can be classified by following ways, Depending on the product of hydrolysis. Depending on Physical properties. On the basis of test with chemical reagents On the basis of Hydrolysis: Monosaccharides:  The simple form of carbohydrates. A carbohydrate that can be hydrolyzed only once to break down into simpler units of polyhydroxy aldehyde or ketone is called monosaccharide.  e.g. glucose , fructose , mannose , etc.  Oligosaccharides:  Sugars that o...