Download Biology Bacteria Period 5

Fermentation: necessary to
taste cheese or yogurt. Helpful
bacteria are responsible for the
acidity in beer.
Streptococcus bacteria: one of the harmful
bacteria that may cause disease in humans.
They cause some small infections like strep
throat and pneumonia. Some harmful
streptococci may even cause death. Highly
contagious and can spread through air.
Salmonella bacteria:
causes much of the food
poisoning in the world
• Live in oxygen free environments
• Live in extreme conditions
– Deep ocean hydrothermal vents
– Swamps
– Sea-water evaporating ponds
• They can live there because of the lipids in their
cell membranes of archaebacteria, the
composition of their cell walls, and the sequence
of nucleic acids in their ribosomal RNA.
• Yes, because some types of bacteria can
be very harmful to us and cause diseases
but other kinds of bacteria cure teeth
decay, and help us function daily.
• Bacteria are the microscopic organisms
whose single cells have neither a
membrane bounded nucleus nor other
membrane-bounded organelles like
mitochondria and chloroplasts.
• Bacteria are among the oldest living
organisms on Earth.
• We could not live without some types of
bacteria.
• Some bacteria is helpful to humans. You
can find them in your toothpaste,
deodorant, and gum.