Transcript Bacteria
PROKARYOTES 1 WHAT WE NEED TO LEARN! Key characteristics of members of the kingdom archaebacteria and kingdom eubacteria Structure (how they are built) Type of nutrition and growth Bacteria and disease Useful bacteria 2 KINGDOMS OF BACTERIA Two main groups the Archaebacteria and the Eubacteria What do we already know about these? 3 ARCHAEBACTERIA 4 Extreme Bacteria ARCHAEBACTERIA CHARACTERISTICS 3.5 billion years old Live in extreme conditions Nonpathogenic Differ from eubacteria Cell membranes are built from different types of fats Cell walls are built from different carbohydrates than the eubacteria. There are three main groups Methanogens Extreme halophiles Extreme thermoacidophiles/thermophile 5 EUBACTERIA 6 True Bacteria EUBACTERIA CHARACTERISTICS - ENERGY Eubacteria get their energy and nutrition in many different ways Aerobic and anaerobic Anaerobes is any organism that does not require oxygen for growth ex. Clostridium butyricum Aerobes require oxygen Producers Photosynthetic Chemosynthetic Consumers Symbiotic Parasitic Saprophytic 7 GENERAL CHARACTERISTICS OF BACTERIA Bacterial shapes Bacillus – rod shaped Coccus- spherical Spirilla – corkscrew Staphylococci – clusters of cocci bacteria Streptococci- chains of cocci bacteria Reproduction asexually by binary fission 8 BINARY FISSION http://www.youtube.com/watch?v=DY9DNWc qxI4 9 STRUCTURE OF BACTERIAL CELLS Smaller than plant and animal cells Have cell membranes that surround their cytoplasm Inside the bacterial cells there is a chromosome, ribosomes and sometimes an extra circular piece of DNA called a plasmid No cell membrane-bound organelles (prokaryotic) 10 OTHER FEATURES OF BACTERIA Endospores- some bacteria are able to produce spores that are capable of withstanding harsh conditions. Motility- some bacteria move by use of a flagella. Some spiral shaped bacteria move by a corkscrew motion, others can contract and slide along ex. Myxobacteria Some eubacteria are pathogenic 11 E. COLI MOVING http://www.youtube.com/watch?v=2P9hvlsF9_ c 12 TYPES OF EUBACTERIA Eubacteria can be divided into at least 12 phyla’s, we will look at 4 First 3 major divisions based upon cell wall 1. Mycoplasma No cell wall Smallest microorganisms capable of independent growth. Some are pathogenic causing pneumonia in humans and cattle 13 2. Gram positive bacteria Thick cell walls Widespread in soil and air Used in the preparation of food products such as sauerkraut, buttermilk, and yogurt Some are a source of antibiotics Responsible for tooth decay 3. Gram Negative bacteria Thin Cell wall -Tend to be antibiotic resistant Responsible for strep throat Many are photosynthetic and anaerobic 14 4. Cyanobacteria Blue/green bacteria – photosyntheticcontain chlorophyll but it is not in a chloroplasts Aerobes Can cause green color in polluted lakesbloom Helped put oxygen in primitive atmosphere 15 PATHOGENIC BACTERIA Some eubacteria cause disease Enter the body in a number of ways Some produce toxins Bacterial infections can be treated with antibiotics(cure) and vaccines(preventative) Safety of the foods we eat have improved due to pasteurization, radiation, canning, refrigeration, FDA, etc 16 BENEFICIAL BACTERIA Some Why? bacteria produce antibiotics. Answer: Antibiotics inhibit the growth of other rival bacteria Bacteria are decomposers – saprophytes. They recycle nutrients and rid our world of dead material. ex. nitrogen and carbon Some bacteria can be used to clean up environmental pollutants and wastebioremediation – ex. Oil spills 17 BENEFICIAL BACTERIA (CON’T) Help produce some of the foods we eat such as yogurt, sour cream, cheese, sauerkraut, sugar syrups….. Used in the production of medicines, enzymes, cleansers and adhesives. Methane produced by bacteria is used as fuel. 18