The Cell Theory (AQA AS Biology) : Revision Note

The Cell Theory

• Until microscopes became powerful enough to view individual cells, no-one knew for certain what living organisms were made from

• A scientist called Robert Hooke is thought to be the first person to view cells (including single-celled microorganisms) and Hooke also came up with the term "cells" to describe these newly discovered structures

• Matthias Schleiden and Theodor Schwann were two other scientists who studied animal and plant cells

  • In 1837, they came up with the idea that all living organisms are made of cells

  • This idea is known as ‘cell theory’

  • The cell theory is a unifying concept in biology (it is universally accepted)

• The cell theory includes three main ideas:

  • All living organisms are made up of one or more cells

  • Cells are the basic functional unit (i.e. the basic unit of structure and organisation) in living organisms

  • New cells are produced from pre-existing cells