Review: What is the definition of a cell? – Basic unit of function and structure of ALL living things. Cell Theory – Holds true for ALL living things. – 3 parts 1. All living things are made of cells 2. Cells are the basic unit of structure and function in living things 3. Living cells come only from other living cells

Cells come in 2 basic types… Prokaryotic cells and Eukaryotic cells – What each term means: Karyo=kernal=nucleus Pro=before Eu=good – prokaryote=before there were ever any nuclei in cells – Eukaryote= has a good nucleus

Prokaryotic cells Organisms with prokaryotic cells are called prokaryotes – organisms without a cell nucleus (= karyon), or any other membrane-bound organelles. Most are unicellular, but some prokaryotes are multicellular. – Earliest and most primitive form of life on earth. (approx 3 billion years ago) First life on earth

Prokaryotes (continued) All prokaryotes are essentially unicellular bacteria. Prokaryotes are able to live and thrive in various types of environments including extreme habitats such as hydrothermal vents, hot springs, swamps, wetlands, and the guts of animals. Bacteria What is bacteria

Louis Pasteur (mid 1800’s) Father of microbiology – Microbiology is the study of tiny (microscopic) life forms such as viruses, bacteria, algae, or fungi. – Known for his discoveries of Vaccinations microbial fermentation pasteurization (preservation of milk) Before Pasteur, people did not believe in microorganisms. People thought Pasteur was crazy. Super old movie but very interesting Life of Louis Pasteur

Eukaryotic cells Organism that has a cell nucleus and whose cells are organized into complex structures by internal membranes. – Basically any cell that has a nucleus – You are made of eukaryotic cells. All animal cells are eukaryotic. – Tip to remember: Eu=you Organisms that are made of eukaryotic cells are called eukaryotes

Prokaryotes were the only form of life on Earth for millions of years until more complicated eukaryotic cells came into being through the process of evolution.Earth All multicellular organisms are eukaryotes, including animals, plants and fungi.animalsplantsfungi Eukaryotic cells are generally much bigger and have more organelles than prokaryotic cells First evolved approx 2 billion years ago