5 Important Biological Molecules

Carbohydrates are the most important organic molecules in nature. It is composed of carbon, oxygen and hydrogen. In carbohydrate, structure of carbon atoms are normally arranged in a ring and this ring linked with the oxygen as well as hydrogen atoms.

Carbohydrates are provide glucose in body and this glucose is converted into energy which is use for many functions and physical activity.

A simple and single sugar unit called as a monosaccharides like glucose, fructose and galactose. When two sugar link together and expels a molecule of water, this linkage bond called as glycosidic linkage.

When two monosaccharides link to form disaccharide, it means two sugar. e.g. sucrose, maltose and lactose. Long chains of many monosaccharide called polysaccharide. e.g. starch, glycogen and cellulose. Polysaccharides consist large number of monosaccharide molecules.

Function Of Carbohydrate : –

Carbohydrate participate in the structure of cell membrane and cellular function such as cell growth, adhesion and fertilization.
Carbohydrate are important for many organic compounds like fats, amino acid.
They are structural compounds of many organisms.
Carbohydrate is a source of energy to do cellular activities in body.
Carbohydrate provides a form of energy storage in body.
Carbohydrate is an integral part of the structural DNA and RNA.

Classification Of Carbohydrates : –

Monosaccharides :- Monosaccharides (Greek: mono-one) are the single unit and simplest group of carbohydrate. It is also called as simple sugar. The monosaccharides are divided into different categories, which is based on the functional group and carbon atoms ex. glucose, glyceraldehyde, ribose, fructose, dihydroxyacetone, ribulose.
Oligosaccharides :- Oligosaccharides (Greek : oligo-few) contain 2-10 monosaccharide molecules which are separate on hydrolysis. Ex . maltose, sucrose, lactose.
Polysaccharides :- Polysaccharides (simple glycans) consist many group of monosaccharides or their derivatives, attach together by glycoside bond. Ex. starch, dextrin, inulin, glycogen, cellulose and chitin.

2) Amino acid and proteins :-

Amino acid is a group of organic compounds and it containing two functional group called amino and carboxyl. Amino acids contain carbon, hydrogen, oxygen and nitrogen.

In general 20 amino acids are used to building blocks of protein. Amino acids is use in human protein synthesis.

The protein is derived from a Greek word proteion, meaning holding the first place. The proteins are found in every part of the cell and it is about 50% of the cellular weight.

When two amino acids join up, it expels a molecule of water and the resulting bond is called a peptide bond. A protein consists of many amino acid joined together to form long chains. Proteins can use as an alternative energy source.

Function Of Proteins :-

Protein performs variety of specialized and essential function in the living cells.

Structural functions :- Certain proteins are responsible for structure and strength of body.

Dynamic functions :- Proteins act as enzymes, membrane receptor and responsible for muscle contraction, blood clotting, respiration, hormones function.

3) Lipids :-

Lipids (Greek: lipos-fat) is most important and much strong from of energy in body. Lipid play important role in cellular structure and various other biochemical function.

Lipid is insoluble in water and soluble in organic solvent (alcohol, ether). Lipid protect the body part and able to store energy.

Lipids are made up of carbon, hydrogen and oxygen atoms. Lipid molecules are strongly hydrophobic (water hating) in nature and therefore lipids do not mix with water.

Classification Of Lipids :-

A . Simple Lipids :-

Esters of fatty acids with alcohols.

(a) Fats and oils (triacylglycerols) : These are esters of fatty acids with glycerol. Oil is a liquid while fat is a solid at room temperature.
(b) Waxes: Esters of fatty acids : It contain with alcohols other than glycerol. These alcohols may be aliphatic or alicyclic.

B . Complex (or Compound) Lipids :-

These are esters of fatty acids with alcohols containing additional groups such as phosphate, nitrogenous base, carbohydrate and protein etc.

(a) Phospholipids :- They contain phosphoric acid and a nitrogenous base.
(b) Glycolipids :- These lipids contain a fatty acid, carbohydrate and nitrogenous base.
(c) Lipoproteins :- Made up of droplets of fats and it surrounded by a single layer of phospholipid molecules.
(d) Other complex lipids :- Sulfolipids, aminolipids and lipopolysaccharides are among the other complex lipids.

C . Derived Lipids:

Derived lipids include glycerol and other like alcohols, fatty acids, mono/ diacylglycerols, lipid steroid hormones, hydro soluble vitamins, carbons and ketone bodies.

D . Miscellaneous Lipids:

These include a large number of compounds possessing the carotenoids.

E . Neutral Lipids:

The lipids which are uncharged form and referred as neutral lipids.

Functions of Lipids

Lipid is a source of fat-soluble vitamins like A,D,E and K.
Lipids are important for cellular metabolic regulations.
Lipids is a storage of energy and it regulate the membrane structure permeability.
Lipids help to protect the internal organs. It give shape and smooth appearance to the body.

4) Nucleotides :-

Nucleic acids :- There are two types of nucleic acid, namely deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). These are the largest molecules in the body.

History :-

DNA was discovered in 1869 by johann friedrich Miescher, a swiss researcher. The DNA contained genetic information was discovered in 1944, by Avery macleod and macCary.

Functions Of Nucleic Acids :-

It is act as reserve bank of genetic information. DNA responsible for maintaining the identity of different species of organisms over millions of years.

5) Enzymes :-

Enzymes and proteins are act as catalysts for biochemical reaction. Catalyst increases the rate of chemical reaction without changing process.

Enzymes may be defined as biocatalysts and it synthesized by living cells.

Historical Background :-

Berzelius, in 1836 made the term catalysis (Greek: to dissolve). In 1878, Kuhne used the word enzyme (Greek: in yeast) to indicate the catalysis taking place in the biological systems.

Isolation of enzyme system from cell free extract of yeast was achieved in 1883 by Buchner. He named the active principle as zymase (later found to contain a mixture of enzymes), which could convert sugar to alcohol. In 1926, James Sumner first achieved the isolation and crystallization of the enzyme.

Classification Of Enzymes : –

Oxidoreductases :- Enzymes involved in oxidation-reduction reactions.
Transferases :- Enzymes that catalyze the transfer of functional groups.
Hydrolases :- Enzymes that bring about hydrolysis of various compounds.
Lyases :- Enzymes specialised in the addition or removal of water, ammonia and C02 etc.
Isomerases :- Enzymes involved in all the isomerization reactions.
Ligases :- Enzymes catalysing the synthetic reactions (Greek: ligate—to bind)

Balance Diet Include :- Carbohydrate, Proteins, Nitrogenous Food, Fats, Vitamins, Mineral Salt and Water.

Important Biological Molecules Are

1) Carbohydrates :-