The Cell Theory Obj: Identify the 3 parts of the cell theory Explain how a specific scientist contributed to the cell theory

What is a Cell? Smallest basic unit of all living things Organisms are either: Unicellular—made of one cell such as bacteria or amoebas Multicellular—made up of many cells such as plants and animals

The Cell Theory All living things are made of cells Cells are the smallest basic unit of life All cells arose from pre-existing cells

Contributors Robert Hooke Anton van Leuwenhoek Discovered cells in cork in 1665 Anton van Leuwenhoek Father of microscopy Discovered single organisms (in pond water) in 1673 Schleiden and Schwann (1838 and 1839) Schleiden—plants are made up of cells Schwann—animals are made up of cells Rudolf Virchow (1855) All cells came from other cells

Prokaryotes Pro—before Kary—nucleus Prokaryotes=before a true nucleus No membrane bound organelles (just ribosomes) No nucleus Smaller than eukaryotic cells Came before eukaryotes Single stranded and circular DNA All bacteria are prokaryotes

Eukaryotes Eu—true Kary—nucleus Eukaryotes=have a true nucleus Nucleus with a nuclear envelope Bigger and more complex than prokaryotes Have membrane bound organelles Double stranded DNA in form of chromosomes Can be uni or multicellular Examples: animals, plants, fungi

Similarities Contain all 4 biomolecules (carbs, lipids, proteins and nucleic acids) Ribosomes DNA Metabolism Can be unicellular Have plasma membrane or cell wall