Transcript Cell Theory PPT

Cell Theory and Cell
Study
The
The Cell Theory
cell is the basic unit of
structure of all living things.
All living things are made up of
cells.
The cell is the basic unit of
function of all living things.
Cells come from pre-existing
cells.
Exceptions to the Cell Theory
These
are facts that can not be explained
by the Cell Theory.
Viruses are not made up of cells, but they
do contain genetic material.
The first cell could not have arisen from a
previously existing cell, Scientists don’t
know the origin of the first cell.
History of Cell Study
Scientists
did not know much about cells
until the discovery of the microscope.
Cells are so small they can not be seen w/o
a microscope.
Anton van Leeuwenhoek- Dutch naturalist
(1600’s). Developed the first microscope.
Robert Hooke- English (1665) was the first
to develop a compound microscope. He
came up with the term cell.
History cont…..
 Robert
Brown- (1831) discovered the nucleus of
the cell.
 Matthias Schleiden- (German, around 1830’s) a
Botanist, concluded that all plants were made up
of cells.
 Theodor Schwann- (German, worked during the
same time as Schleiden), studied animal cells.
Concluded that animals were made up of cells.
 Rudolf Virchow- (1858) concluded that all new
cells must come from previously existing cells.
The Compound Microscope
 Microscopes
are used to study materials that can’t
be seen with the naked eye.
 Microscopes use two lenses (compound
microscope) to increase the size of a specimen.
 A specimen must be thin enough for light to pass
through it.
 The total magnification of an object is found by
multiplying the magnification of the objective x
the magnification of the eyepiece.