Biomolecules- Carbohydrates, Proteins, Nucleic acids and Lipids

A biomolecule is a chemical compound found in living organisms or a molecule produced by a living organism. Biomolecules have a wide range of sizes and structures. Biomolecules are mainly classified into two types micromolecules and macromolecules. Instead of micromolecules and macromolecules, they are called small and large molecules, or organic and inorganic molecules. Macromolecules contain small-sized, low molecular weights between 18 and 800 daltons. Minerals, water, sugars, amino acids, and nucleotides will come under macromolecules. Macromolecules are large-sized and have a high molecular weight. These are above 10000 daltons. Carbohydrates, lipids (fats and oils), proteins, and nucleic acids will come under macromolecules. Macromolecules are formed by polymerizing subunits called monomers, except lipids. Macromolecules are alternatively called polyanions. A biomolecule is generally identified based on its molecular form, and a chemical equation usually represents a molecular form.

Macromolecules are organic compounds. They join together to form larger molecules. They have molecular weights of less than 1000 daltons.

Minerals

Minerals are the essential micromolecules that maintain the health of the body. Muscles, bones, hearts, and brains function correctly with the help of minerals. Minerals are found in many foods or as supplements.

Water

Water is an inorganic micromolecule. It is found in its free form. Two hydrogen atoms and one oxygen atom will combine to form water.

Sugar

Sugars are combined, forming carbohydrates. Sugars contain only carbon, oxygen, and hydrogen.

Amino acids

R-CH(NH2)COOH, where R represents the variable side chain group

Amino acid is a monomer that makes proteins. Amino acids are organic molecules that contain an amino group, a hydroxyl group, and a carbon side chain. There are 20 amino acids in micromolecules. Micromolecules of amino acids vary in terms of polarity, charge, molecular weight, and functions. Depending upon the relative position of the amino group with respect to a carboxyl group, amino acids are again divided into α, β, γ, δ and so on, and depending upon the relative number of amino and carboxyl groups in their molecule, amino acids can also be divided as acidic, basic, or neutral.

Nucleotide

It is the basic building block of nucleic acids. Each and every species of every generation resembles its ancestors in many ways, and the nucleus of a living cell is responsible for this transmission of inherent characteristics. The particles in the nucleus of the cell, responsible for heredity, are called chromosomes, and these are made up of proteins and another type of biomolecule called nucleic acids. Phosphate-sugar-base, where the base can be Adenine (A), Thymine (T), Guanine (G), or Cytosine (C).

Carbohydrates

Carbohydrates are also called polysaccharides. They are made up of simple sugars such as glucose, fructose, and galactose. Complex carbohydrates like starch and glycogen are made up of long chains of glucose molecules. Carbohydrates are also involved in the structural components of cells and organisms, such as the cell walls of plants and the exoskeletons of insects.

Cane sugar(sucrose), glucose [C6H12O6], starch, etc. are some examples of carbohydrates. Some of the carbohydrates, which are sweet in taste, are also called sugars. The general formula for carbohydrates is Cx(H2O)y, usually considered as carbon hydrates.

Based on their behaviour during hydrolysis, carbohydrates are classified into monosaccharides, oligosaccharides, and polysaccharides.

• A carbohydrate which cannot be hydrolysed further to give a simpler unit of polyhydroxy aldehyde is called a monosaccharide.

Based on the number of carbon atoms and the functional group present in them Monosaccharides are further classified into different categories. For example, if a monosaccharide contains an aldehyde group, it is known as an aldose, and if it contains a keto group, it is known as a ketose.

• Carbohydrate that yields two to ten monosaccharide units, on hydrolysis are called oligosaccharide

• polysaccharides is the carbohydrates which yield a large number of monosaccharide units on hydrolysis.

Lipids

Lipids are another important class of biomolecules that play a crucial role in the structure and function of cell membranes. They are insoluble in water and include fats, oils, waxes, and steroids. Lipids with a higher melting point are usually solids at room temperature and are called fats or waxes; at a lower melting point, they are usually liquids at room temperature and are called oils. Lipids store energy in the body, insulate organs and tissues and act as signalling molecules. Fats and oils are made up of fatty acids and glycerol, while waxes are made up of long-chain fatty acids and alcohol.

Proteins

Proteins are the most important biomolecules in living organisms; milk, cheese, pulses, peanuts, fish, meat, etc. are a few examples of foods that contain protein. Proteins are polypeptide chains, which are generally made up of amino acids. Amino acids are further divided into two kinds.

1. Essential amino acids

2. Non-essential amino acids

Glycine, alanine, and serine are examples of amino acids. Proteins are mainly used to fight against infectious organisms and transport nutrients across the membrane. Based on the structure of the protein, it is classified into four types.

1. Primary structure

2. Secondary structure

3. Tertiary structure

4. Quaternary structure

The primary structure is the basic structure of the protein. Secondary structure protein threads form a helix. The tertiary structure is folded upon itself like a hollow woollen ball. In the quaternary structure, each polypeptide develops its tertiary structure and functions as a protein.

Basis of their molecular shape Proteins can be classified into two types

1. Fibrous proteins: When the polypeptide chains run parallel and are held together by hydrogen and disulphide bonds, a fibre-like structure is formed which is called Fibrous protein.

2. Globular proteins: When the chains of polypeptides coil around to give a spherical shape Globular proteins are formed.

Nucleic acid

Nucleic acids are large biomolecules. A significant function of nucleic acids is the storage and expression of genomic information. Nucleic acids are one of the most important macromolecules for life. They will carry the genetic blueprint of a cell and have instructions for the functioning of the cell. The two examples of nucleic acids are deoxyribonucleic acid and ribonucleic acid.

Deoxyribonucleic acid (DNA): C10H12N2O4, also written as (C5H5N5O)n where n is the number of nucleotide units in the DNA strand

Ribonucleic acid (RNA): C10H12N2O5P, also written as (C5H4O)n(C10H12N2O)nP where n is the number of nucleotide units in the RNA strand

ATP (Adenosine triphosphate)

ATP is a biomolecule that functions as the primary energy source for cellular processes in living organisms. It consists of a nucleotide base (adenine), a sugar molecule (ribose), and three phosphate groups. The high-energy phosphate bonds between the phosphate groups store energy that can be used by cells to power various processes, such as muscle contraction, nerve impulse transmission, and chemical synthesis. ATP is synthesized during cellular respiration and is used immediately, so it is constantly recycled in the cell. The chemical formula for ATP is C10H16N5O13P3.