1. Cells & Heredity: Section 1.1 – Discovering Cells 6 th Science

2.  Cells – the basic units of structure and function in living things  The microscope was invented around 1590 and made it possible for people to discover and learn about cells  Microscope – an instrument that makes small objects look larger  All microscopes have at least one lens  Compound microscope – a light microscope that has more than one lens

3.  Robert Hooke – one of the first people to observe cells  Anton van Leeuwenhoek – first person to observe bacteria (he called them armalcules, meaning “little animals”)  Matthias Schledein – concluded that all plants are made of cells  Theodor Schwann – concluded that all animals are made up of cells  Rudolf Virchow – proposed that all cells come from other cells

4.  Cell Theory:  All livings things are composed of cells  Cells are the basic unit of structure and function in living things  All cells are produced from other cells

5. Microscopes  Magnification: the ability to make things look larger than they are  In a light microscope, lens or lenses magnify an object by bending the light that passes through them  Convex lens – a lens that has a curved shape where the center of the lens is thicker than the edges and is called a convex lens  Because a compound microscope uses more than one lens, it can magnify an object even more

6.  Resolution – the ability to clearly distinguish the individual parts of an object  Electron microscopes – use a beam of electrons instead of light to examine a specimen  the resolution of electron microscopes is much better than the resolution of light microscopes