Biomolecules are the biochemical molecule present in organisms that are essential in different biological processes.

E.g., carbohydrate, fatty acids | cell division, replication

• Biomolecules include macromolecules such as lipids and carbohydrates, protein.
• Biomolecules are generally endogenous and exogenous.
• Endogenous: produced inside the organism.
• Exogenous: need to be taken such as vitamins.
• Most of the biomolecules are organic compounds.

What is an organic compound?

• Organic compounds are the compound that contains Carbon, Hydrogen, Oxygen, and Often Nitrogen, Phosphorus, and Sulfur.
• Commonly, biomolecules contain four elements: Nitrogen, carbon, hydrogen, and oxygen.
• These elements make up to 96% of the total mass of the human body.
• Carbon is an essential compound because it can form a long chain and help to form a backbone for biomolecules.

Types of biomolecules

• Fatty Acid, Sterols, Monosaccharides, Lipids, Vitamins, Metabolites, Nucleic acids
• Polymers, oligomers, and monomers.

FATTY ACIDS

• These are the building blocks of our body fat.
• Contain a long aliphatic chain.
• Fatty acids are of two types

Based on saturation: saturated and unsaturated.

Based on length: SCFA (short-chain fatty acids), MCFA (medium-chain fatty acids), LCFA (long-chain fatty acids)

• Fatty acid exists as phospholipids, triglycerides, and cholesterol.

Saturated fatty acids:

• No double bond between carbon.
• CH3(CH2)nCOOH

Unsaturated fatty acids:

• Have one or more carbon double bonds C=C.

CARBOHYDRATES

• The term derived from French Hydrate de Carbone.
• Carbohydrates are the organic molecules contain C, H, and O
• The ratio of hydrogen and oxygen is 2:1 (H2O).
• Carbohydrates are the chief source of energy for all living things.
• There are three types of carbohydrate:

1. Monosaccharides, Disaccharides, and Polysaccharides.

• Monosaccharides: single sugar compounds e.g., glucose
• Disaccharide: 2 molecules of simple sugar E.g., maltose
• Polysaccharide: 3 or more sugars Also known as complex sugar. E.g., Starch

LIPIDS

• Lipids are the organic compounds of C, H, and O but the ratio is not fixed.
• Fatty acids are the building blocks of lipids.
• Commonly 3 fatty acids combine with a glycerol molecule and form Triglyceride.
• Lipids are the long-term source of energy.
• Lipids help in building cell membranes

PROTEINS:

• Proteins are the organic compound consist of C, H, O, and N.

1. Functioning in:

• Structural components in the cell.
• Some proteins work as receptors or messenger.
• Defend against diseases (antibodies).
• Acts as a biological catalyst (enzymes) in biochemical reactions.
• Every enzyme is a protein, but every protein isn’t an enzyme.
• Amino acids are the building blocks of proteins.
• An amino acid consists of a center carbon bonded with H, R (alkyl group), amino group, and carboxylic group.
• Amino acids joined together with a peptide bond to form a macromolecule (polypeptide) or a giant protein.
• There are nine essential amino acids:

Histidine, isoleucine, methionine, lysine, leucine, phenylalanine, valine, tryptophan, threonine.

• Non-essential amino acids (11)
• Arginine, tyrosine, cysteine, glycine, proline, asparagine, glutamine, serine, ornithine, alanine, and aspartate.

NUCLEIC ACID:

• Nucleic Acids made up of C, H, O, N & P
• Contains genetic information (parent to progeny).
• DNA and RNA
• Consisting of the sugar-phosphate backbone.
• Nucleoside are the building blocks of Nucleic Acids
• A nucleoside consists of a phosphate group and a nitrogenous base and 5 carbon ribose sugar.
• Nitrogenous bases are of two types: Purines and Pyrimidine