Microbiology

Viruses, Bacteria, Fungus, Parasites

Bacteria

• A prokaryotic single-celled organism. (No nucleus).

• Genetic info is in the cytoplasm.

• Has a flagellum (tail) to move

Bacteria Reproduction

• Bacteria can reproduce sexually or asexually.

• Asexually – one parent or binary fission.

• Sexually – both bacteria share genetic information called conjugation.

• ***Can grow and divide rapidly

Bacteria Everywhere

• Bacteria can live everywhere- with or without oxygen, hot or cold.

• Larger than a virus.• It is living because it

can make it’s own food and reproduce.

Bacteria Harmful or Helpful

• Harmful: Can cause sickness or disease like strep throat or food poisoning.

• Helpful: Involved in oxygen, food production, recycling, environmental cleanup, and medicine production.

BacteriaAntibiotics

• Antibiotics are used to inhibit the growth of bacteria.

• Since antibiotics have been overused, many diseases are becoming harder to treat.

Antibiotic Resistance• Mutated bacteria

survive an antibiotic treatment and become a resistant population to treatment.

Virus

• Smallest of all microbes.• Protein Coat & Inner

Core(genetic material) OR outer membrane lock & key.

• Non-living – they do not have the characteristics of life like reproduction, make food or waste.

Virus AIDS Virus• Viral diseases are

the most widespread illness in humans. (mild fever to some cancer to fatal diseases)

Virus Reproduction

• Hepatitis B Virus • Do not reproduce

sexually or asexually. Viruses invade a “host” cell and force it to reproduce and multiply.

Virus» Flu Virus

• When they invade the healthy cell, the virus will use the enzymes and organelles of the host cell to make more viruses, usually killing the healthy cell in the process

Virus Harmful & Helpful

• Harmful: Can have deadly affects on people. Can get very sick with no cure.

• Helpful: Used for gene therapy by allowing virus to enter host cell

• Bird Flu

Virus

• There is NO cure for viruses…only can treat the symptoms like coughing or runny nose.

• Vaccine and some anti-viral drugs are used to control and prevent the spread of disease.

Fungi• Fungi are

eukaryotic, multicellular heterotrophs(they do not make their own food).

Fungi Reproduction

• Fungi reproduces sexually and asexually. This provides an adaptative advantage…

Favorable environment: rapid asexual reproduction.

Environmental stress: sexual reproduction ensures genetic recombination for adaptation to new conditions

Fungi Helpful & Harmful• Harmful: fungal diseases

in humans like ring-worm or athlete’s foot, or nail fungus. Fungal diseases in plants like cotton, rice soybeans. Mold spores become airborne-

• Helpful: environmental recycling, food production (bread) and medicine like penicillin