MP

• Abiogenesis

  • Believed that the animalcules came into being as a result Of decomposition Of plant or animal tissue
• Biogenesis

  • Argued that Leeuwenhoek's animalcules came from parents, as do higher form of life

  • This idea that the already existing animalcules produced offspring
• Taxonomy - The science of taxonomy includes the classification , nomenclature, and identification of living organisms.
• Taxa - Place organisms that share certain common characteristics into taxonomic groups
• Eucaryotic Cell - Has the presence of many intercellular membranes that compartmentalize the cell into a number of discrete organelles
• Procaryotic Cell

  • It is bounded by a plasma membrane but has no other separate membrane-bound organelles
  • The type of cell represented by the bacteria and the cyanobacteria
• Yeast -

  • The microscopic one-celled fungi characteristically reproduced by forming buds on the mother cell which, when mature, pinch off to become new single yeast cell
  • Majority of them produce sexual pores following the fusion of two separate cells
  • Many yeasts convert carbohydrates to ethyl alcohol Saccharomyces cerevisiae
• Molds

  • they are multi-cellular and considerably more complex than yeast
  • Many molds become visible as "mildew" on clothes, foods...
  • It develops characteristically by branching, hair-like growths, and most form both sexual and asexual spores

       Some molds are responsible for the flavor Of fine (aged) cheese
• Sarcinae - Cells divide in three planes, in a regular pattern, producing a cuboidal arrangement of cells
• Medical Microbiology - The study of microorganisms that cause disease in humans and animals It is concerned with epidemiology how the organism is spread from one infected host to another knowing specifically how the microorganism causes disease after gaining entry to the host
• Immunology

  • The study of host reaction to a foreign substance (invading microorganism) in the body

  • It is no longer confined to the study of infectious diseases but also includes: allergic reactions adverse reaction to organ transplant immunity to malignant (cancer) cells.
• Industrial Microbiology

  •       Involves a large variety of microbial activities

  •       Many commercial products are products of microbial activities such as: alcoholic beverages organic solvents antibiotics
• Agricultural Microbiology

  • Encompasses the study of microorganisms that are either harmful or beneficial to the production Of agricultural products
  • Interested in diseases of plants and livestock, and role of bacteria in soil fertility
• Communicable Disease - Transmitted from one person to another
• Contagious Disease - A communicable disease that is easily transmitted from one person to another
• Epidemic Diseases - If a greater-than-expected number of cases of a given disease arises suddenly in a specific area over a specific period
• Pandemic - An epidemic that affects several countries or continents
• Endemic Diseases

  • Are those that are present in a population or   community at all times

  • They usually involve relatively few people during a specified time
• Herd Immunity - When a high proportion of a population has developed immunity to a specific infectious agent
• Exogenous Microbes

  • Originate from sources outside the body

  • Usually, humans and exogenous microbes live together in harmony

  • However, if something disrupts this harmonious relationship, the microbes may cause an infection
• Causative Agents - A causative agent for infection is any any microbe capable of producing disease
• Reservoir

  • Is the environment Or object in or on which a microbe can survive and, in some cases, multiply.

     Inanimate objects, human beings, and other animals can all serve as reservoirs, providing the essential requirements for a microbe to Survive at specific Stages in its life cycle

     Human reservoir can be a case or carrier
• 1.  Incubatory Carrier

        One who is incubating the illness

        Has acquired the illness but does not yet show symptoms

        Incubation periods vary from one infectious organism to the next
• 1.  Convalescent Carrier

        Is in the recovery of an illness but continues to shed the pathogenic organism A person who has Salmonella infection commonly sheds the organism in feceseven after symptoms disappear
• 3. Intermittent Carrier

  Occasionally sheds the pathogenic organism

  Some people are intermittent carriers of S. aureus
• 1.  Chronic Carrier

        Always has the infectious organism in his system

        Some people are chronic carrier o f hepatitis B, their blood harbors the hepatitis B surface antigen for years
• Portal of Exit

     Is the path by which an infectious agent leaves its reservoir

  Usually, this portal is the site where the Organism grows
• Mode of Transmission

      The means by which the infectious agent passes from the portal of exit in the reservoir to the susceptible host
• Direct Contact

  Refers to person-to-person spread of organisms through actual physical contact
• Indirect Contract

  Occurs when a susceptible person comes in contact with a contaminated object
• Droplet

  Transmission

  Results from contact with contaminated respiratory secretions

  It differs from airborne transmission in that the droplets don't remain suspended in the air but settleto surface
• Airborne Transmission

  Occurs when fine microbial particles

  containing pathogens remain suspended

  in the air for a prolonged period, and

  then are spread widely by air currents

  and inhaled
• Vehicle

  A substance that maintains the life of

  the microbe until it is ingested or

  inoculated into the susceptible host

  The vehicle is not harmful in itself but

  may harbor pathogenic microbes and

  thus serve as an agent of transmission
• Vector-borne Transmission

  When anintermediate

  carrier, or vector

  such as flea or a

  mosquito, transfer

  a microbe to

  another living

  organism

  It is of most

  concern in tropical

  areas, where

  insects commonly

  transmit disease
• Pathogenicity - Refers to a microbe's ability to cause

  pathogenic changes, or disease
• Virulence

  Refers to the degree of a microbe's

  pathogenicity

  It can vary with the condition of the

  body's defense

  Virulence can be enhanced by several

  factors:
• Dose

  A microbe must be present in a

  sufficient dose to cause human disease
• Invasiveness (Infectivity)

  Refers to the ability of a microbe to

  invade tissues

  Some tissue can enter the human body

  through intact skin, other can penetrate

  through a break in the skin or mucous

  membrane
• Toxigenicity

  Refers to a microbe's potential to

  damage host tissue by producing and

  releasing toxins

  Some bacteria release exotoxins that

  are quickly disseminated in the blood,

  causing systemic and neurologic

  manifestations
• Viability

  Refers to the ability of a microbe to

  survive outside the body

  Microbes can live and multiply in a

  reservoir, which provides what the

  microbes need to survive

  The microbes can then be transmitted

  from the reservoir to another person