Molecular Biology

Molecular biology is a branch of biology that deals with the composition, structure, and function of cellular molecules like proteins and nucleic acids essential for the cellular functions and mechanisms.

Molecular biology is primarily focused on nucleic acids like DNA and RNA, their structure, composition, expression, and interactions among themselves.
Molecular biology is slowly becoming an important area of research with the discovery that nucleic acids and other biomolecules play a vital role in the normal functioning of the body.
Molecular biology developed as a separate discipline from other branches like biochemistry, genetics, and biophysics.
Over the years, many techniques have been developed in molecular biology; however, researchers tend to use methods and techniques native to genetics.
Common techniques used in molecular biology include X-ray diffraction and electron microscopy for the determination of the three-dimensional structure of nucleic acids.
The discipline focuses on the molecular mechanism of genetic processes so that genes can be used for genetic engineering to isolate, modify, and sequence genes.
Initial studies in molecular biology were involved in the determination of three-dimensional structures of proteins in order to understand their structure and mechanism of action and expression.
Initial studies in molecular biology were based on the rapid growth and readily manipulable genetics of simple bacteria, such as E. coli, and their viruses.
More recently, not only the fundamental principles but also many of the experimental approaches first developed in prokaryotes have been successfully applied to eukaryotic cells.
Current advances in recombinant DNA technology have made even the determination of the complete sequence of the human genome a feasible project.
Complete genome sequencing of various living beings, including humans, has been done with modern approaches like DNA sequencing techniques and PCR.
Studies of molecular biology have also been applied in clinical research and medical therapies, both of which are covered under gene therapy.
Molecular biology also plays a vital role in studies related to regulations of various parts of a cell, which can then be used to target new drugs and diagnose diseases efficiently.

Phenol-Chloroform Method of DNA Extraction: Principle, Steps, Applications

July 17, 2026June 30, 2026 by Sandeep Shakya

The phenol-chloroform method of DNA extraction is the technique that separates nucleic acids from proteins and other cellular components by exploiting their different solubilities in water and organic solvents. After … Read more

DNA Quantification Using Nanodrop: Principle, Steps, Uses

July 11, 2026June 26, 2026 by Sandeep Shakya

DNA quantification is a fundamental step in molecular biology, ensuring that downstream applications such as PCR, qPCR, sequencing, cloning, and restriction digestion are performed with optimal template input. Among the … Read more

cDNA Synthesis from RNA: Principle, Steps, Uses

July 18, 2026June 24, 2026 by Sandeep Shakya

The principle of cDNA synthesis revolves around using a DNA polymerase that can interpret an RNA template to generate a complementary DNA strand. Reverse transcriptase catalyzes the addition of deoxynucleotide … Read more

DNA Quantification Using a Spectrophotometer: Principle, Steps, Uses

July 11, 2026June 23, 2026 by Sandeep Shakya

Accurate quantification of DNA is a fundamental requirement in molecular biology, biotechnology, and biomedical research. Many downstream applications, such as polymerase chain reaction (PCR), restriction digestion, cloning, sequencing, and next-generation … Read more

DNA Fingerprinting: Principle, Methods, Applications

July 20, 2026June 5, 2026 by Sagar Aryal, PhD

Principle of DNA Fingerprinting Methods of DNA Fingerprinting Restriction fragment length polymorphism (RFLP) and polymerase chain reaction (PCR) amplification of short tandem repeats (STRs) are two main DNA tests widely used … Read more

37 Types of PCR with Definition, Principle, and Uses

July 20, 2026June 3, 2026 by Anupama Sapkota

Types of PCR (Polymerase chain reaction)- definition and uses

List of Types of PCR 1. Amplified fragment length polymorphism (AFLP) PCR 2. Allele-specific PCR 3. Alu PCR 4. Assembly PCR 5. Asymmetric PCR 6. COLD PCR 7. Colony PCR … Read more

Allele-Specific PCR: Principle, Steps, Types, Examples, Uses

July 20, 2026May 13, 2026 by Gayathri Krishnankutty

PCR involves three main steps: Denaturation, Annealing, and Extension. To make the method more efficient and specific, variations of the method have been developed, one of which is allele-specific PCR, … Read more

Amplified Fragment Length Polymorphism PCR (AFLP-PCR)

May 16, 2026May 12, 2026 by Gayathri Krishnankutty

Amplified Fragment Length Polymorphism PCR (AFLP-PCR) is a DNA fingerprinting technique that selectively amplifies restriction fragments generated from digested genomic DNA to detect genetic polymorphisms and create unique genomic fingerprints. … Read more

Anchored PCR: Principle, Steps, Types, Examples, Uses

May 15, 2026May 11, 2026 by Gayathri Krishnankutty

Anchored PCR is a modified PCR technique used to amplify and characterize unknown DNA sequences adjacent to a known DNA region by using one sequence-specific primer and one non-specific anchor … Read more

Competent Cells: Applications, Preparations, Troubleshooting

April 12, 2026 by Susmita Baniya

Competent cells are cells (bacteria, yeast, etc.) that have been altered to take up exogenous foreign DNA from the environment. While some bacteria can undergo transformation naturally, common laboratory strains … Read more