Page 10 - Demo 1

Lesson 1 Cell Theory, Cell Structure,

and Cell Funcons

Source: http://www.hipsci.org/img/cellhome.jpg

L e a r n i n g O b j e c t i v e s

At the end of this lesson, you must be able to:

1 .explain the postulates of the cell theory,

2 .disnguish prokaryoc from eukaryoc cells, and
3 .describe the structure and funcon of major subcellular

organelles.

THE CELL THEORY

The cell theory is one of the basic principles of biology. This theory
posits that every living thing is made up of cells as its basic unit of structure.
Because cells are so small, no one had observed them unl the mid-seventeenth
century when microscopes were invented.
Robert Hooke, an English experimental scienst, was first to describe the
cell in a 1665 publicaon called Micrographia. He built a microscope – one that

2