aim: what are the characteristics of bacteria? bacteria antonie van leeuwenhoek discovered bacteria...
DESCRIPTION
Bacteria Antonie van Leeuwenhoek discovered bacteria Are in the air, foods, surfaces of things we touch Found underground and at the great depths of the oceans Lives in your body Some like extreme temperatures-live in hot springs Others live in cold water, or acidic water, or salty waterTRANSCRIPT
BacteriaAntonie van Leeuwenhoek discovered
bacteriaAre in the air, foods, surfaces of things
we touchFound underground and at the great
depths of the oceansLives in your bodySome like extreme temperatures-live in
hot springsOthers live in cold water, or acidic
water, or salty water
Structure of BacteriaSmaller than plant or animal cellsOne-celled that occur alone, in chains
or groups3 basic shapes:1.Spheres:
Called cocci2.Rods:
Called bacilli3.Spirals
Called spirilla
Contains cytoplasm surrounded by cell membrane and a cell wall
Prokaryotic-no membrane-bound organelles and nucleus
Genetic material is located in the one circular chromosome
Ribosomes found in cytoplasm
Special FeaturesSome bacteria has a thick, gelatinlike
capsule around the cell wallHelps protect the bacteria from being
destroyedHelps it stick to surfaces
Some have hairlike projections on its surfacehelps them stick to surfacesSlime layer also helps them stick
Those who live in moist places have a flagellaHelps them move
ReproductionReproduces by fission
Simplest form of asexual reproduction2 new cells with genetic material
identical to the original cell are producedSome reproduce through a process
similar to sexual reproduction2 bacteria line up next to each otherExchange DNA through a tubeResults in cells with different
combinations of genetic material-may give them an advantage on surviving
Obtaining Food and EnergySome make their food
Contain chlorophyll and use the Sun’s energy
Others use energy from chemical reactions
Called producersSome get it from their environment
Most are consumersBreak down dead organisms Live as parasites
Aerobe-uses O2 for respirationMost bacteria are aerobes
Anaerobe-is adapted to live without O2Several kinds of this bacteria live in
the digestive tract of humansSome can’t survive in areas with O2
EubacteriaGrouped according to their:
cell shapestructureway they obtain foodtype of food they consumeWastes they produceMethod used for cell movementWhether its an aerobe or anaerobe
Some are producersCyanobacteriaMake their own food used CO2, water,
and energy from the sunProduce oxygen as a wasteContain chlorophyll and a blue
pigmentKnown as blue-green bacteriaSome are yellow, black or red
live together in long chains or filamentsMany covered with gelatinlike
substance-able to live in coloniesAre an important source of food for
some organismsCan cause problems for aquatic lifeSome are consumers
Grouped based on whether they are gram-positive or gram-negative
Composition of the cell wall can determine how it will react to antibiotics
ArchaebacteriaFound in extreme conditions, such
as hot springsOne of the first organisms on EarthGrouped based on
Where they liveHow they get energy
Some live in salty environmentsSome live in acidic or hot
environments
Some are methane producersLive in muddy swamps, intestines of
cattle and humansAnaerobicUse CO2 for energyRelease methane as a wasteUsed to breakdown sewage material
Benefits of bacteriaSome bacteria is responsible for
producing vitamn K- necessary for blood clotting
Some help digest food in the large intestine
Some produce antibioticsBacillus produces antibiotic found in antiseptic ointments
Bacterial found in the soil produces streptomycin
Some are saprophytes- help recycle nutrientsUsed in sewage plants to break down wastes in CO2 and H2O
Nitrogen-fixing bacteriaChange nitrogen in the air to forms that plants and animals can use
Animals and plants need nitrogen to make proteins and nucleic acids
Saves farmers millions of dollars in fertilizer
Bioremediation-using organisms to help clean up or remove environmental pollutantsUses bacteria to breakdown wastes and pollutants into simpler harmless compounds
Other bacteria use certain pollutants as a food source
Only 5%-10% of wastes are treated through this process
Scientists researching to make it faster
Used in the production of foodsYogurtCheesesSauerkrautSoy saucepickles
Used to make medicines, enzymes, cleansers and adhesives
Methane gas that is released by many bacteria can be collected and used as fuel
Harmful BacteriaPathogens-any organism that causes
diseaseBacterial pathogens can cause illness
and diseaseEnter through cut in the body, or inhale
themOnce in your body they multiplySome produce toxins-Ex: BotulismSome bacteria have endosperms that
enable them to adapt to harsh environments
All food contains bacteria unless it was sterilized
One way to kill bacteria is through pasteurization
Usually treated with antibioticsExample: penicillinVaccines can prevent bacterial
diseases