Bacteria

Bacterial Video Video

Bacterial Kingdoms 1.Archaebacteria   Called “Ancient” bacteria  Live in harsh environments- volcanic vents, hot springs, salty water  Require little or no oxygen  Methanogens  produce methane gas

Bacterial Kingdoms Methanogens  Get energy by changing H 2 & CO 2 into methane gas Found in swamps, sewage treatment plants, digestive tracts of animals

Bacterial Kingdoms 2. Eubacteria   True bacteria  Largest and most diverse  Found everywhere  Heterotrophic  Aerobic or anaerobic

Bacterial Structure  microscopic prokaryotes (no nucleus)  can fit 1,000 to 10,000 in the diameter of a dime

Bacterial Structure

Bacterial Nutrition feed on dead organic matter Parasites – feed on a host cell Photoautotroph – use sunlight to make food such as iron or sulfur to make foodChemoautotroph – oxidize inorganic matter such as iron or sulfur to make food

Bacterial Respiration 1. Some are obligate aerobes  Require oxygen to live EX.  Mycobacterium tuberculosis 2. Some are obligate anaerobes  Die if oxygen is present EX.  Clostridium botulinum 3. Some are facultative anaerobes  Need Oxygen but aren’t killed by it EX.  Escherichia coli

Bacterial Shapes 1.Bacilli   rod shaped bacteria  E. coli., Bacillus Anthracis, Clostridium Botulinum

Bacilli

Bacterial Shapes 2. Cocci   spherical shaped bacteria  Arranged in clusters  Streptococcus, staphylococcus

Cocci – Staph on Skin

Staph Infection

Bacterial Shapes 3. Spirilla   spiral shaped bacteria  Borrelia burgdorferi

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Bacterial Movement  Move by flagella, sliding on layer of slime, wiggle like snakes

Bacterial Reproduction  Under proper conditions, bacteria can reproduce every 20 minutes.  3 ways

Bacterial Reproduction 1.Binary fission   Asexual reproduction  C’some replicates and cell divides  All new cells are identical  No exchange of genes

Bacterial Reproduction 2. Conjugation   Protein bridge forms between two bacteria and genes are exchanged  sexual reproduction  New cells not identical

Bacterial Reproduction 3. Spore formation   Thick wall which encloses DNA and cytoplasm  Protects bacteria against hostile environments (endospore)  “come back to life” when favorable  Difficult to kill

Bacteria and Disease Louis Pasteur   First person to show that bacteria cause disease  Developed what is known as Germ Theory of Disease

Bacteria and Disease Two ways bacteria cause infection  1.Attacks cells and tissues of body and use them for nourishment 2.Release poisons that interfere with body functions

Bacteria and Disease Two ways to fight bacteria 1.vaccine  prevents infection from getting started – only sometime 2. Antibiotics  drugs that can destroy bacteria

Bacterial Diseases  Strep throat, tuberculosis, typhoid fever, tetanus, lyme disease, food poisoning, ulcer, MRSA, and many more

Benefits of Bacteria 1.Decomposers and recyclers 2.symbiotic relationships  situation where both organisms benefit EX.  E.coli in intestines

Benefits of Bacteria 3. Fertilizers  convert nitrogen into a chemical that plants can use through a process called nitrogen fixation. EX.  legumes - nuts

Benefits of Bacteria 4. make foods such as cheese, yogurt, vinegar 5. Breakdown sewage – Rid –X 6. Degrade oil

Controlling Bacteria 1.Sterilization  using heat to kill bacteria 2. Food storage  slow the growth 3. Food processing  boiling, frying, steaming 4. Physical Removal  washing hands or surfaces, surgery 5. Disinfectants  chemicals

Bacterial Shapes

Controlling Bacteria 1.Sterilization  using heat or chemicals to kill bacteria  autoclave 2. Refrigeration  prevents bacteria from reproducing

Bacterial Structure 1.Cell wall  protects and gives shape; made of carbs - peptidoglycan 2.Outer membrane  protects against some antibiotics

Bacterial Structure 3. Cell membrane  regulates what enters 4. Cytoplasm  contains the organelles 5. Plasmid  circular piece of DNA

Bacterial Structure 6. Genetic material  circular DNA molecule 7. Flagellum  hairlike structure that moves the bacteria

Bacterial Structure 8. Ribosome  makes proteins 9. pili  short appendages  Adhere bacteria to surfaces

Bacterial Cell Wall  Very important; used to classify bacteria  Single or double

Bacterial Cell Wall  Identified using gram staining. Gram staining  If purple appearance under a microscope, bacteria have single cell wall (gram positive) If red appearance under a microscope, double cell wall (gram negative)

Bacterial Structure