Download Discovery of Cells

Discovery of Cells
7th Grade Science
What is a CELL?
• Cell – the basic unit of all living
things.
• Cells are SO tiny… they are not
visible to the naked eye.
Robert Hooke – discovered ‘cells’
• Using a microscope, Hooke discovered small boxes in
a piece of cork.
• He called these CELLS.
• He continued his work by examining mainly plants. He
thought cells were found only in plants.
Cork cells… resembles a
honeycomb.
Anton van Leeuwenhoek
• Using a microscope , began to examine
different animals.
• He looked at pond scum, blood cells from
fish, birds, and frogs, and blood from
humans.
• He was the first person to discover
bacteria AND determined cells were in
both, plants and animals.
Pond Scum
The Cell Theory
• All organisms are composed of
one or more cells.
• The cell is the basic unit of life in
all living things.
• All cells come from existing cells.