Transcript Bacteria

MICROBES !!!
Bacteria and Viruses
Bacteria:
Classification and Structure
What are the 6 Kingdoms?
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Archaebacteria
Eubacteria
Protists
Fungi
Plants
Animals
Classification of Bacteria
• Archaebacteria: extremists
• Eubacteria:
–Heterotrophs
–Photosynthetic autotrophs
–Chemosynthetic autotrophs
Archaebacteria
• Live in extreme
locations:
– Oxygen-free
environments
– Concentrated
salt-water
– Hot, acidic
water
Eubacteria - Heterotrophs
• Found everywhere
• Parasites: live off of other
organisms
• Saprobes: live off of dead
organisms or waste (recyclers)
Eubacteria: Photosynthetic
Autotrophs
• Photosynthetic: make their own
food from light
• Cyanobacteria: blue-green,
yellow, or red
• ponds, streams, moist areas
Eubacteria: Chemosynthetic
Autotrophs
• Get energy by breaking down
inorganic substances like sulfur
and nitrogen
• Make nitrogen in the air usable
for plants {Very Important}
Structure of Bacteria
• Two parts to Bacteria Structure:
–Arrangement
–Shape
Arrangement
• Paired: diplo
• Grape-like clusters: staphylo
• Chains: strepto
Shape
• Rod: bacillus
• Spheres: coccus
• Spirals: spirillum
Examples
• Streptococcus: chains of spheres
• Staphylospirillum: Grapelike
clusters of spirals
• Streptobacillus: Chains of rods
Bacterial Diseases
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Pneumonia
Strep Throat
Meningitis
Salmonella
Cholera
Bubonic Plague
Treatment
• Bacterial infections can usually be treated
by using antibiotics.
– The first antibiotic was Penicillin which was
discovered by Alexander Fleming in 1928.
– Penicillin is derived from a fungus and works
by eating holes in the cell wall of the bacterial
cells
Viruses
Alive?
• Viruses are non-living!
– They do not carry out respiration.
– They do not grow or develop
– Cannot reproduce without a host cell
Viral Structure
• Inner Core
– Contains nucleic acid
(DNA or RNA) with
instructions for making
copies of the virus
• Outer protein coat
called a capsid
• May have an
additional layer of
protein called an
envelope
Viral Structure
• 4 major shapes of
virus
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Helical
Polyhedral
Studded Envelope
Polyhedral with leglike extensions
Viral Reproduction
• Lytic Cycle (eg. The flu)
– Very Fast (about 30 minutes)
– Takes over host cell’s genetic material
– Kills the host cell quickly
• Lysogenic Cycle (HIV virus, herpes simplex 1)
– Not fast
– A provirus is formed-it becomes part of the host cell’s
chromosome
– Changes the host cell, doesn’t kill it quickly
– Can enter the lytic cycle at any time, usually because of
some sort of stress
Lytic Cycle
Lysogenic Cycle
Viral Diseases
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Herpes
Chicken Pox
Influenza
Meningitis
Measles
Mumps
Treatments for Viral Diseases
• Vaccines- alert the immune system without
causing the illness
• Anti-viral drugs
• Many have no cures but simply medicines
to control symptoms