Cell theory

Robert Hooke

• first to demonstrate, illustrate cork cells in his book Micrographia.

• first person to use the term ‘cell’.

Anton Van Leeuwenhoek

• first person to observe blood cells and sperm cells with microscope.

• introduced the first unicellular organism ‘animalcules’.

Matthias Schleiden

discovered plant cells

Theodor Schwann

Discovered animal cells

Rudolf Virchow

proponent of the 3rd postulate.

FIRST POSTULATE

all living organisms are composed of one or more cells.

SECOND POSTULATE

cell is the basic unit of life in all living things.

THIRD POSTULATE

all cells come from pre-existing cells (mitosis, meiosis)

Microscopy

science of magnification and resolution

factors affecting resolution:

1. wavelength of light used

2. numerical aperture

early microscope

• 6x-10x magnifying power

• 1590

Zaccharias Jansen, Hans Jansen

• 9x magnification (first)

• made the microscope

Anton Van leeuwenhoek

first man to use a real microscope in biology