2.6 What the Cell?

An introduction to the cell theory &

discovery

Cells! Who wants some?!Not that type, but this kind…

Cells have a lot of variety and some exists as living, mobile entities

But first, a brief history of the cell…Robert Hooke, an Englishman, was looking at cork through a basic microscope and saw tiny chambers which he called “cells”. This occurred in 1665.

Close to the same time, a Netherlander, named Leeuwenhoek (LEE-van-hook) used a microscope to observe living, one-celled creatures in drinking water. Yum.

Cell Theory and Discovery

• Cell Discovery

• Many scientists contributed to the discovery of cells and the cell theory.

Cells … cork 1665

2) ‘animalcules’1) Improved lens 1674

1676

16833) Discovered bacteria

Plants made of cells1838

Animals made of cells

Cells come from cells1855

1839

And hence the Cell Theory was born……………….

1) The cell is the basic unit of structure and function of organisms

2) All living things are composed of one or more cells

3) All cells come from cells

• All cells share certain characteristicscertain characteristics

» All cells tend to be microscopicmicroscopic

» All cells are enclosed by a membranemembrane

» All cells are filled with cytoplasmcytoplasm