M&Pwk2AB

• Microbiology is the branch of biology that studies microorganisms and their effects on humans
• Microorganisms is a collection of organisms that share the characteristic of being visible only with a microscope
• Microorganisms contribute to the quality of human life (maintain the balance of chemical elements in nature ; breakdown the remains of all that die ; recycle carbon, nitrogen, sulfur, phosphorus and other elements)
• some microorganisms cause infectious disease called Pathogenic (It overwhelm body systems by sheer force of numbers ; produce powerful toxins that interfere with body physiology; viruses inflict damage by replicating themselves within tissue cells causing tissue degeneration)
• Taxonomy is the science of classification
• Taxonomy is the science of classification ▫ Kingdom (5 major divisions) ▫ Phylum (groups of related Classes) ▫ Class (groups of related Orders) ▫ Order (groups of related Families) ▫ Family (groups of related Genera) ▫ Genus (groups of related Species) ▫ Species (living organisms that are alike)
• The 5 Kingdoms

  (Monera, Protista, Fungi, Plantae, and animalia)
• Monera (unicellular prokaryotes: bacteria, cyanobacteria, blue-green algae)
• Protista (unicellular eukaryotes: protozoa, unicellular algae, slime molds)
• Fungi (multicellular eukaryotes: molds, mushrooms, yeasts)
• Plantae (multicellular eukaryotes: plants)
• Animalia (multicellular eukaryotes: animals)
• Species is a population of individuals that breed among themselves
• species are microorganisms that are 70% similar from a biochemical standpoint
• Microorganisms and all other living organisms are classified as Prokaryotes and Eukaryotes
• Prokaryotes is/are lack a nucleus ; lack organelles ; include bacteria and cyanobacteria (blue-green algae)
• Eukaryotes have a nucleus ; have organelles ; include fungi, protozoa and simple algae
• Viruses are neither Prokaryotes or Eukaryotes
• Viruses are lack the characteristics of living things
• Viruses are able to replicate only in their host (living cells)
• In mid 1600s, the English scientist Robert Hooke viewed cells and observed strands of fungi
• 1670s – Dutch merchant Anton van Leeuwenhoek made a simple one-lens microscope and observed and provided accurate descriptions of protozoa, fungi and bacteria
• 1875-1900 is The Golden Age of Microbiology
• Theory of Spontaneous Generation, a long-held theory that life springs up from non-living or decaying organic matter, was based on observations of rotting food seemingly producing living organisms. Francesco Redi (1626-

  1678) was an Italian physician who showed that rotting meat carefully kept from flies will not

  spontaneously produce maggots.
• The germ theory in 1861: Louis Pasteur's famous experiments with swan-necked flasks finally proved that microorganisms do not arise by spontaneous generation. This led to the Development of sterilization
• In 1890s, Robert Koch sets guidelines for how to prove that a particular microbial agent is responsible for a particular disease.
• bacteria is derived from a Latin and a Greek word Bakteria meaning “cane”(Rod)
• Bacteria is a microorganism with few micro meter in length and have wide range of shapes (round, oval, rod and spiral shapes).
• Bacteria is First discover by Antony Van Leeun Hook in 1676, initially called “Animalcules”
• Study about bacteria is known as “Bacteriology”, while study about the harmful effect of bacteria on human body is known as “Medical bacteriology”.
• Bacteria are found everywhere on earth i.e., in soil, water, air, deep earth crust, radioactive waste and acidic hot spring
• A single gram of soil contains 40 million bacteria while a million bacteria found in an ml of fresh water.
• However only few of these are harm full to human body causes disease
• Bacteria produce more Oxygen than plants
• Bacteria are earlier form of life form on earth.
• Their (Bacteria) fossils are found 2.5 billion years ago
• Size of bacteria range between 0.5 to 5 micrometer
• Bacteria are prokaryotic microbes (have no membrane bounded Nucleus and mitochondria)
• Bacteria have a single chromosome as Genetic material
• Bacteria Enclosed in a rigid cell wall made up of peptidoglycane