3 Groups of Archaea: Correct Answers - Species found in non-
extreme environments
- They're everywhere
- Methane-producing species
- Species in extremely harsh environments
Accidental Discovery of Penicillin (1928) Correct Answers
Alexander Fleming observes mold had contaminated bacterial
culture
- Mold has a bacteria-free circle around itself
- Referred as "Zone of Inhibition"
Bacteria Cell Walls Correct Answers Important feature of
nearly all bacteria
- Maintains cell shape
- Protects cell
- Prevents cell from bursting into hypotonic environment
Cell Wall has: Correct Answers Peptidoglycan, a mesh of
polymers and cross-linked peptidoglycan
- Cell wall of Archaea lacks peptidoglycan
Endotoxins Correct Answers Lipopolysaccharide components
of membrane of gram-negative bacteria
- EX: Salmonella typh (causes typhoid fever) and other
Salmonella species cause food posioning
Exotoxins Correct Answers Proteins secreted by certain
bacteria
, - Clostridium botulinum (causes botulism)
- "Please inject this into my face!"
- Vibrio cholerae (causes cholera)
- Stimulates cells in intestine to release chloride ions, resulting
in severe dehydration
Extreme Halophiles Correct Answers Lives in hypersaline
environments
- Some in water up to 10X saltier than seawater:
- Ocean Salinity ≈ 35.2 g/kg
Extreme Thermophiles Correct Answers Lives in extremely hot
environments
- Some require temperatures above boiling
- Why do these temperatures make it impossible for most
species to survive?
- Enzymes are denatured
- What adaptation must these Archaea have?
- Specialized Enzymes
Facultative Anaerobe Correct Answers Survives with or
without O2
- Opportunistic
Gram - Negative Bacteria Correct Answers Has less
peptidoglycan and an outer membrane
- Includes well-known member of genus: Salmonella
- Stain = Pink
Gram - Positive Bacteria Correct Answers Has simpler walls
with large amounts of peptidoglycan