Cell theory

Cell theory is widely accepted theory that explain the life. There are five contributors to the cell theory: 1. Robert Hooke. 2. Anton van Leeuwenhoek. 3. Matthias Schleiden. 4. Theodor Schwann. 5. Rudolf Virchow. In 1838, German botanist, Matthias Schleiden observed that all plants are made of different kinds of cell that form the tissues […]

Why onions make you cry ?

Onions make us cry because onion releases a chemical called as Propanethiol S-oxide that irritates our eyes. It is sulfur-containing volatile chemical that enters into the eyes and stimulates lachrymal glands to release tears. Propanthial s-oxide is a type of defence mechanism in onion plant that are used to protect the plant from being consumed […]