Bacteria

2 Kingdoms  Archaebacteria  Eubacteria

Archaebacteria  Unicellular autotrophs  All anaerobic (without oxygen)  All live in extreme environments

Archaebacteria  Divided into 3 groups according to where they live

Group 1  Oxygen-free environments, produces methane  Ex:Deep-sea, water sewage, cow stomachs

Group 2  Concentrated salt water, purple pigmented  Ex: Great Salt Lake, Dead Sea

Group 3  Hot, acidic waters of sulfur springs  Almost-boiling sulfuric acid

Eubacteria  Grouped into 3 primary groups according to how they get nourishment

Heterotrophs  Parasites  Saprobes (decomposers)

Photosynthetic Autotrophs  Get energy from the sun  Cyanobacteria (most are blue-green, but some are red or yellow)

Chemosynthetic Autotrophs  Get energy from the breakdown of inorganic (non- living) substances

Bacterial Structures  Prokaryotic (no nucleus)  DNA in a single circular chromosome

Bacterial Structures  Classified by cell shapes and grouping

Bacterial Shapes  Spheres (coccus)

Bacterial Shapes  Rods (bacillus)

Bacterial Shapes  Spirals (spirillum)

Bacterial Groupings  Pairs (diplo-)  Clusters (staphylo-)  Chains (strepto-)

Bacterial Groupings  Pairs (diplo-)

Bacterial Groupings  Clusters (staphylo-)

Bacterial Groupings  Chains (strepto-)

Environmental Needs  Bacteria require very little in order to survive.  However ideal conditions include moist environments with specific temperature ranges and adequate supply of nutrients

Metabolism  Most bacteria require oxygen (obligate aerobes)  Some bacteria are killed by oxygen (obligate anaerobes)

Protection  Endospores – structure produced by bacteria that contains a copy of its DNA; covered by a thick wall which resists drying out, boiling, & chemicals

Protection, cont’d  endospores

Protection, cont’d  Toxins – poisons produced to ward off predators and to digest food particles

Reproduction  Bacteria use two processes to reproduce.

Binary fission  Asexual reproduction similar to mitosis  One cell makes Two

Conjugation  Sexual reproduction where one bacterium transfers all or part of its genetic material to another

Application  Why do you get sick if you don’t cook your food long enough?