Avatar for Sourav PanSourav Pan

Academic Writer, Microbiology Specialist | M.Sc. Microbiology, Calcutta University, Founder of Biologynotesonline.com
Sourav is the founder and sole author of Biology Notes Online. He holds a Master’s degree in Microbiology from Calcutta University and has over 5 years of experience in academic writing, life science content creation. His content reflects hands-on lab expertise, deep subject knowledge, and a strong passion for simplifying biology for students. Whether it’s genetics, microscopy, or metabolic pathways — Sourav explains it in a way that’s accurate, exam-focused, and easy to remember. He regularly updates and fact-checks all the material published on this site, ensuring students get trustworthy and updated biology notes with references to real scientific sources.

Contribution of Ignaz Semmelweis, Hans Christian Gram, Charles Lavaran, Fanny Hesse, Marjory Stephenson, Kiyoshi Shiga, Emil von Behring.

• • 15 min readby
Contribution of Microbiologist

1. Ignaz Semmelweis Ignaz Semmelweis was a Hungarian physician and obstetrician (1818–1865). He is regarded as the “savior of mothers”. He worked in a maternity clinic in Vienna where high maternal deaths were observed after childbirth. It was during this period that he studied the cause of puerperal fever. Key Contributions of Ignaz Semmelweis Some … Read more

Contribution of Microbiologists: Joseph Lister, Alexander Fleming, Edward Jenner, Lazzaro Spallanzani, Martinus Beijerinck.

• • 21 min readby
Contribution of Microbiologists

1. Joseph Lister Joseph Lister was a British surgeon and medical scientist. He was born in Essex, England in 1827 in a Quaker family. He is regarded as the father of modern surgery and father of antiseptic surgery. He obtained the degree of Bachelor of Medicine from University College London in 1852. His main work … Read more

Contributions of Antonie van Leeuwenhoek

• • 13 min readby
Contribution of Antonie van Leeuwenhoek

Who was Antonie van Leeuwenhoek? Antonie van Leeuwenhoek was a Dutch scientist who is regarded as the Father of Microbiology. He was born in 1632 in Delft, Netherlands. He did not receive formal higher education and he spoke only Dutch. He started his career as a linen draper. In this work he used small magnifying … Read more

Contribution of Louis Pasteur in Microbiology.

• • 14 min readby
Contribution of Louis Pasteur

Who Was Louis Pasteur? Louis Pasteur was a French chemist and microbiologist who is regarded as one of the founder of modern bacteriology and microbiology. He was born in 1822 at Dole in France. His work is considered as the foundation of microbiology and immunology. In the early period of his career, he studied chemistry, … Read more

Contribution of Robert Koch and Koch’s Postulates

• • 11 min readby
Robert Koch and Koch’s Postulates

Who was Robert Koch? Heinrich Hermann Robert Koch (1843–1910)was a German physician and microbiologist. He is regarded as one of the founder of modern bacteriology. He is most famous for discovering the specific bacteria causing deadly infectious diseases. Anthrax is caused by Bacillus anthracis. Tuberculosis is caused by Mycobacterium tuberculosis. Cholera is caused by Vibrio … Read more

The Germ Theory of Disease – Experiments, Principles, Key Figures

• • 16 min readby
Germ Theory of Disease - Spontaneous Generation

What is Germ Theory of Disease? Germ theory of disease is a scientific theory. It states that many infectious diseases are caused due to invasion of host organism by microscopic pathogens (germs). These germs are not seen by naked eye. These pathogens includes bacteria, viruses, fungi and protozoa. The germs enters in body and then … Read more

Types of Crystals in Urine – Causes, Factors, Identification

• • 13 min readby
Types of Crystals in Urine

Crystals in urine is the condition in which solid crystalline particles are seen in urine. It is referred to as crystalluria. These crystals are formed when urine contains excess amount of minerals and waste products and they are precipitated out as solid particles. In normal conditions, kidneys filter blood and different dissolved solutes are excreted … Read more

Mode of Transmission of Diseases

• • 11 min readby
Transmission of Disease

Transmission of diseases is defined as the process by which an infectious agent is transferred from its natural habitat (reservoir) to a new susceptible host. It is the movement of pathogens from one individual to another or from environment to human. This process is an essential part of the chain of infection. Without transmission the … Read more

Urinary Tract Infection (UTI) – Pathogenesis, Treatments, Diagnosis, Prevention

• • 17 min readby
Treatment of Urinary Tract Infections with D-Mannose

What is Urinary Tract Infection (UTI)? Urinary Tract Infection (UTI) is a common bacterial infection of urinary system. It is affecting any part of the urinary system which includes bladder, urethra, ureters and kidneys. It is most frequently caused by Escherichia coli (E. coli). It occurs more often in women than in men. UTI is … Read more

Bt Crops – Definition, Types, Advantages, Limitations

• • 19 min readby
The mechanism of Bt toxicity

What are Bt Crops? Bt crops are the transgenic crops in which a gene from the soil bacterium Bacillus thuringiensis is introduced into the plant. It is the gene that produces special insecticidal proteins inside the plant body and these proteins are referred to as Cry or Vip proteins. When insect larvae feed on the … Read more