Bacterial Processes

Food Source Respiration Reproduction

Favorable conditions Survival

Food Source

• Photosynthesis – make food using sunlight energy

Food Source

• Chemosynthesis – make food using energy from inorganic chemicals

Hydrogen sulfide

Food Source

• Parasites – living on or in another living organism

Food Source

• Saprophytes – live on a dead organism and decompose it

Respiration

• The breakdown of glucose (food) to release energy

Aerobic Anaerobic

Respiration

• Aerobic – use O₂

Respiration

• Anaerobic – don’t use O₂

hydrogen sulfide and methyl mercaptan

Reproduction

Asexual Sexual

Most bacteria can reproduce either way

Reproduction

• Asexual – binary fission (split in two) – most common means of reproduction

Reproduction

• Sexual – produce genetic variety

Conjugation Transformation

Conjugation

• The exchange of genetic material (plasmids) between 2 cells

Conjugation Example

• http://www.hhmi.org/biointeractive/bacterial-conjugation

Transformation

• Absorption of DNA from the environment

Favorable Conditions

• Warmth• Moisture• Darkness• Food

Survival

• Endospores – a dormant stage of a bacterium to survive unfavorable conditions

Advantage over others?

Endospore

Negative Effects of Bacteria

Pathogenic – disease causing

Bacterial Diseases of Humans

Strep throat

Diptheria

Staph Infection

Tetanus

Gangrene

Pink Eye

Acne

Tooth Decay

Viral or Bacterial Disease?• Tetanus

Viral or Bacterial Disease?• Smallpox

Viral or Bacterial Disease?• Measles

Viral or Bacterial Disease?• Pinkeye

Viral or Bacterial Disease?• Warts

Viral or Bacterial Disease?• Tooth decay

Viral or Bacterial Disease?• Staph Infection

Viral or Bacterial Disease?• AIDS

Viral or Bacterial Disease?• Strep Throat

Viral or Bacterial Disease?• Mono

Viral or Bacterial Disease?• Common Cold

Viral or Bacterial Disease?• Acne

Bacterial Diseases

• Endotoxins – poisonous chemicals inside the bacteria that aren’t released until the bacteria die

• Example – typhoid fever, UTI

Bacterial Diseases• Exotoxins – poisonous chemicals released

from living bacteria as waste

• Example – acne, tetanus

Food Spoilage

• Bacteria eat the food and release bad tasting and/or poisonous chemicals

Prevention

• Refrigerate, freeze, boil and seal, dehydrate, salt

Benefits of Bacteria

Human Body

• E. coli lives in the colon and breaks down food

Human Body

• Bacteria cover our skin and eat bad organisms

Fuels

• Bacteria produce alcohol and methane which are burned for energy

Foods

• Bacteria help make cheese, cottage cheese, and yogurt

Other

• Clean up oil spills

Other

• Sewage treatment

Other

• Make medicines

Insulin

antibiotics