Cells and Cell Theory

Leeuwenhoek • 1673-1723 Anton van Leeuwenhoek Saw “wee beesties” and “animalcules” He is known as the “Father of Microscopy described live microorganisms observed in teeth scrapings, rain water,and peppercorn infusions.

The First Observations –Robert Hooke 1665 Used a compound microscope (2 lenses) Looked at cork under microscope composed of little boxes or cells Named what he saw, “cells” .

Schleiden & Schwann Development of the CELLTHEORY • Matthias Schleiden (1838) German Botanist – using a microscope proposed that all plants are composed of cells • Theodor Schwann (1839) German Zoologist – using a microscope proposed that all animals are composed of cells • Together they stated: – Cells are the elementary particle of all living organisms – All cells are alive – independent to the organisms to which they belong

Virchow German pathologist He is known as the “Father of Pathology • 1858, Rudolf Virchow said cells arise from preexisting cells. German pathologist He is known as the “Father of Pathology

Cell Theory Cell Theory * • All living things are composed of one or more cells • Cells are the basic units of structure and function in an organism • Cells come only from the reproduction of preexisting cells * Named for the Monk prayer cells

Cells Eukaryotic versus Prokaryotic Cells • Prokaryotic - Cells lacking a nucleus. • Eukrayotic - Cells containing a nucleus. – Organelles - Membrane-bound bodies found within eukaryotic cells.

Types of Cells Two Basic Types of Cells • Prokaryotes: – prounounced: pro-carry-oats • Eukaryotes – Proun: you-carry-oats

Prokaryotes Smaller No true nucleus – loose genetic material Includes Archaea & Bacteria

Eukaryotes Eukaryotes • Larger more complex cells that make up most familiar life forms: plants, animals, fungi, algae • Surrounded by a cell membrane made of lipids