“In the year 1657, I discovered very small living creatures in rain water”

Antonie van Leeuwenhoek, Dutch scientist inventor 1632-1723

Cell is the basic unit of life. There are three main parts to a cell: the nucleus, which contains the genetic material; the cytoplasm, which contains the organelles, the parts which accomplish the normal functions of the cell; and the cell membrane, which regulates what comes into the cell and out. All life contains one or more cells and all cells arise from other cells.

Cell is a building block

Cartesian theory

Mechanistic theory  All life processes were mechanical phenomena and when complex configurations are formed life surfaces.  (descartes was a proponent)

Vitalist View

Irreducible forces  An elemnt in life that was not reducible to physics nor chensistry

History

early microscopists
Malpighi, Marcello (1628-94),
Leeuwenhoek, Antoni van (1632-1723),
Swammerdam

Identified
microscopic structures

did not
recognize
cellular
composition

1665
Hooke
named the
cell
walled compartments of
dead cork tissue

1831
Brown
discovered the
nucleus.

1838
Schleiden
tcell theory’

1839
Schwann
tcell theory’

animals were
composed of
cells

concept of
structural and
functional units

1863
Virchow
body as a
‘cell state,’ with
specialized categories of
cells

1841
Henle
first thorough
account of
human histology.

1830
compound light microscope

1875
Hertwig O.
discovery of
fertilization of the
egg

1876
astigmation was
eliminated from microscopic instrumentation
improvement in
resolution