 Fossil evidence puts the origin of life at least 3.5 billion years ago.  Carbon isotope evidence pushes this date even farther to 3.85 bya.  Life arose within a few hundred million years after the impact of the last major impact of the heavy bombardment

Colonies of bacteria – a mound built of layers of lime-secreting cyanobacteria and trapped sediment found in Precambrian rocks.

 Genetic evidence suggests that all life on earth evolved from a common ancestor which was probably similar to microbes that live today in hot water near undersea volcanic vents or hot springs.  Lab experiments suggest that the first organism may have arisen as a result of natural chemical processes.

 Life on earth thrives in a wide range of environments. All life in general require three things: A source of nutrients A source of energy Liquid water

 The study of microorganisms  Living things that cannot be seen with the naked eye  Viruses, although not living may be included. (virology)

 Prokaryotic and Eukaryotic  Most are unicellular  Some noncellular  Include bacteria, protozoa, fungi, and animalia.  Found in large numbers and various environments

 Prokaryotes have no nucleus.  The nucleoid region in a prokaryotic cell consists of a concentrated mass of circular DNA. This mass of DNA is usually one thousand times less than what is found in a eukaryote.  A prokaryote may have a plasmid in addition to its major chromosome. A plasmid is a small ring of DNA that carries accessory genes.  Usually these genes are for antibiotic resistance!

 Almost all prokaryotes have cell walls external to the plasma membrane.  Cell walls maintain cell shape.  Bacterial Cell walls are composed of peptidoglycan. (Plant Cell Walls are composed of cellulose)

 Widely distributed Soil Water Air Plants Animals (including humans) Extreme environments like hot springs

 Taxonomy Science of classifying organisms  Provides universal names for organisms  Provides a reference for identifying organisms

Domain Kingdom Phylum Class Order Family Genus Species

 Three Domains Eukarya Archaea Eubacteria  Six Kingdoms Archaeabacteria Eubacteria (bacteria) Protista Fungae Plantae Animalia

Domain – Eukarya Kingdom – Animalia Phylum – Chordata Class – Mammalia Order – Primates Family – Hominidae Genus – Homo Species – Homo sapiens

 Kingdom – Bacteria  Phylum – firmicutes  Class – Bacilli  Order – Bacillales  Family – Staphylococcaceae  Genus – Staphylococcus  Species - aureus

 Affect the well-being of our world Agriculture Food production Environmental protection Biochemistry/Medicine  Cause diseases  Spoil foods  Deteriorates materials

 Make full use of the beneficial aspects and avoid and control the detrimental aspects

 Create a table comparing Archaea to Bacteria  How do Archaea and Bacteria benefit life on Earth? (What do they contribute to the environment?)  Give the classification (KPCOFGS) and names (genus and species i.e. Escherichia coli.) of two of Archaea and two bacteria  Due Tomorrow (2/02/16)