The Role of Bacteria in Infection
M. Stafford
What is a Prokaryote?
• Unicellular
• Lacks a nucleus
• Small 1-5 micrometers
Bacteria are Examples of Prokaryotic Cells
• Two Kingdoms
• Eubacteria – found everywhere
• Archaebacteria – found in harsh environments
Shapes of Bacteria
Growth and Reproduction
• Binary Fission
• Conjugation• Spore Formation -
endospore
Importance of Bacteria
• Producers• Decomposers• Many human uses
Soil bacteria
Bacteria and Disease
• Some use cells for food
• Example Mycobacterium causes tuberculosis
• Some release toxins
• Example – Streptococcus
• Releases a toxin that can cause a rash and scarlet fever
• Diphtheria – Corynebacterium diphtheria infects the throat and releases toxins into the bloodstream.
• Destroys tissues can cause heart failure, paralysis and death
Preventing Bacterial Disease
• Your first line of defense against bacterial infection is your skin
• Wash your hands
Preventing Bacterial Disease
• Vaccine – a weakened or killed pathogen that is used to stimulate the body’s immune system
• Antibiotic – blocks the growth and reproduction of bacteria
Fleming - penicillin
Control of Bacteria
• Sterilization by heat• Disinfectants• Food storage and
processing
Video – Killer microbe
• 8 minutes