Biomolecules

Biomolecules are the essential building blocks of all living organisms. These organic compounds primarily consist of carbon, hydrogen, oxygen, and nitrogen. Interestingly, the elements found in the human body are similar to those in the earth’s crust.

Introduction

Biomolecules are vital organic molecules that play a crucial role in the growth and development of living organisms. Key biomolecules include carbohydrates, proteins, lipids, nucleic acids, and enzymes.

Also Check: Human Reproductive System

Carbohydrates

Carbohydrates are the primary source of energy and the most abundant biomolecules in the body. They are produced in green plants through photosynthesis using carbon dioxide, sunlight, and chlorophyll.

Photosynthesis Reaction

nCO₂ + nH₂O + energy -> C_nH_2nO_n + nO₂ where 'n" ranges ffrom 3 to 7

Carbohydrates yield aldehydes and ketones upon hydrolysis and are also called saccharides, meaning sugars. Examples include glucose, fructose, lactose, maltose, starch, cellulose, and glycogen.

Classification of Carbohydrates

By Functional Groups:
- Aldoses: Aldehyde group (e.g., glucose, galactose, ribose)
- Ketoses: Ketone group (e.g., fructose)
- Reducing Sugars: Hemiacetal or hemiketal group (e.g., maltose, lactose)
- Non-Reducing Sugars: No hemiacetal group (e.g., sucrose, raffinose)
By Sugar Units:
- Monosaccharides: Single sugar unit (e.g., glucose, fructose, galactose)
- Oligosaccharides: Two or more monosaccharide units (e.g., raffinose, stachyose)
- Polysaccharides: Long chains of monosaccharides linked by glycosidic bonds (e.g., cellulose, glycogen, starch)

Also Check: Nutrition in Plants

Table 1: Types of Carbohydrates

Type	Example
Monosaccharides	Glucose, Fructose, Galactose
Oligosaccharides	Raffinose, Stachyose
Polysaccharides	Cellulose, Glycogen, Starch

Lipids

Lipids, or fats, are esters of fatty acids and glycerol, releasing high energy upon oxidation. They are nonpolar and dissolve in nonpolar solvents like acetone, toluene, and benzene, but not in water. Examples include wax, sterols, oils, butter, cheese, glycolipids, phospholipids, and certain vitamins.

Also Check: Biogas

Classification of Lipids:

Simple Lipids: Esters of fatty acids and alcohols, soluble in nonpolar solvents (e.g., fats, oils, waxes)
Complex Lipids: Contain additional functional groups besides fatty acids and glycerol, found in cell membranes (e.g., lecithin)
Derived Lipids: Formed from the hydrolysis of simple and complex lipids (e.g., fat-soluble vitamins, cholesterol)

Table 2: Types of Lipids

Type	Example
Simple Lipids	Fats, Oils, Waxes
Complex Lipids	Lecithin
Derived Lipids	Cholesterol, Fat-Soluble Vitamins

Proteins

Proteins are polymers of amino acids linked by covalent polypeptide bonds. They are crucial for structural and functional roles in the body.

Also Check: Biofertilisers

Classification of Proteins:

Primary Structure: Sequence of amino acids
Secondary Structure: Polypeptide chains form helices or sheets through hydrogen bonding
Tertiary Structure: 3D folding of polypeptide chains into hollow spheres
Quaternary Structure: Multiple tertiary structures combine

Table 3: Levels of Protein Structure

Structure Level	Description
Primary	Sequence of amino acids
Secondary	Hydrogen bonds form helices/sheets
Tertiary	3D folding into spheres
Quaternary	Combination of tertiary structures

Nucleic Acids

Nucleic acids store and transmit genetic information. They are made of nucleotide units, each comprising a nitrogenous base, a phosphate group, and a sugar molecule.

Types of Nucleic Acids:

Deoxyribonucleic Acid (DNA): Double-stranded helix with deoxyribose sugar; adenine pairs with thymine, and guanine pairs with cytosine.
Ribonucleic Acid (RNA): Single-stranded with ribose sugar; adenine pairs with uracil, and guanine pairs with cytosine. RNA types include mRNA, tRNA, and rRNA.

Also Check: Biome

Table 4: Types of Nucleic Acids

Type	Structure	Bases
DNA	Double-stranded helix	Adenine, Thymine, Guanine, Cytosine
RNA	Single-stranded	Adenine, Uracil, Guanine, Cytosine

Frequently Asked Questions on Biomolecules

Biomolecules are complex organic compounds essential for the growth and metabolism of living organisms.

The main types of biomolecules are carbohydrates, lipids, proteins, nucleic acids, and enzymes.

Nucleic acids come in two primary forms: DNA and RNA. DNA holds genetic information, while RNA is primarily involved in protein synthesis.

Biomolecules are crucial for the growth and development of organisms. Carbohydrates provide energy, lipids offer insulation and structure to cell membranes, proteins form hormones and enzymes and aid in cell repair and growth, and nucleic acids are the building blocks of genetic material.