BIOMOLECULES
Biomolecules are molecules
that occur naturally in living organisms, include macromolecules
like proteins, carbohydrates, lipids and nucleic acids. However It also includes small
molecules like primary and secondary metabolites and natural products. Biomolecules atoms consists mainly of carbon and hydrogen with nitrogen, oxygen, sulphur, and
phosphorus that are
covalently bound together. Although there is a vast diversity of living organisms. The chemical compositon and metabolic reactions of the organisms appear to similar. The composition of living tissues and non-living matter are appear to be similar in qualitative analysis.Closer analysis reveals that the relative abundance of carbon, hydrogen and oxygen is higher in living system. All forms of life are mainly composed of biomolecules only. All living forms like bacteria, algae, plant and animals are made of similar macromolecules that are responsible for life.
4 MAJOR CLASSES OF BIOMOLECULES
CarbohydrateGeneral formula: (CH2O)x Linkage: Glycosidic bond Carbohydrates (polysaccharides) are long chains of sugars. Monosaccharides are simple sugars. It has free aldehyde or ketone group, acts as reducing agents. Disaccharides made of two monosaccharides. The bonds between two monosaccharides is glycosidic bonds. Monosaccharides and disaccharides are sweet, crystalline and water soluble substances. Polysaccharides are polymers of monosaccharides. It is not sweet, complex carbohydrates and insoluble in water are not crystalline form.. Example: glucose, fructose, sucrose, maltose, starch, cellulose etc. proteinsLinkage: Peptide bonds, Disulfide linkages, and Hydrogen bonding
Functional group: amines, ammonias, carboxyls and 20 remainder groups proteins are heteropolymers of stings of amino acid which join together by peptide bond. in between carboxyl group and amino group of successive amino acid.. protein are form from 20 different amino acid depend on number of amino acid and the sequence of amino acid. -four level of protein structure
|
LipidsLinkages: Ester linkages
Functional group: esters, carboxyls, hydroxol, and hydrocarbons Lipids composed of long hydrocarbon chains hold a large amount of energy and are energy storage molecules. It is generally esters of fatty acids and are building blocks of biological membranes. Most of it have a polar head and non-polar tail. Fatty acids can be unsaturated and saturated. Lipids present in biological membranes are of three classes based on the type of hydrophilic head present.
Nucleic acidsLinkages: Covalent bonds and hydrogen bonds
organic compound with heterocyclic rings made of polymer of nucleotides which consist of nitrogenous base, a pentose sugar, and phosphate group. A nucleoside is made of nitrogenous base attached to a pentose sugar. The nitrogenous bases are adenine, guanine, thyamine, cytosine and uracil. The nucleic have two main parts. The backbone of a nucleic acid is made of alternating sugar and phosphate molecules bonded together in a long chain |