Introduction Flashcards
Midterm
Microbiology
The study of Microoganisms or Microbes
Organisms that cannot be seen by the naked eye: they are microscopic.
Microorganisms
Unicellular (Single cell) entity that can generate energy and grow without the help of others.
Biofilms
Community of microorganisms capable of “talking” to each other to initiate group behavior.
The invention which created the field of microbiology, it’s function and when was it made?
Time in century
Microscope (Beginning of the17th century): was first used for the microscopic observation of microscopic organisms, surfaces, substances, ect.
What did Robert Hooke do?
- Described the microscopic appearance of dry cork as a honeycomb of chambers and named it”cellulae”, hence “cell” (1665).
- Published the first accurate microscopic drawing of a variety of molds.
Who is the “Father of Microbiology” and what did he do?
- Antoni van Leeuwenhoek
- In 1684, published the first drawing of what he called “wee animacules”. The first time microorganisms were seen.
What has been a major cause of mortality and morbidity throughout history but was unknown before the 19th century.
Infectious diseases
Infectious diseases that have influenced politics, economy, religion, science and
literature.
- An outbreak of black death (plague, Yersinia pestis) killed 30-60% of Europe population at the end of the 14c.
- A fungal disease of potatoes (blight, Phytophtora infestans) led to the potato famine in Ireland and more than a million people died of starvation in the 1840s.
- Typhoid fever (Salmonella typhi) contributed to the decline of Athens (430 BC).
Poor medical knowledge prior to the 19th century led to…
- Inaccurate theories to explain the causes/outbreaks of diseases, such as the miasma theory.
- “Witch-hunts” and persecution based on ethnicity and/or religion.
- Use of inappropriate treatments, for example bleeding, which causes more damage.
Spontaneous generation
False hypothesis that some vital force can create living organisms from inanimate
objects. It was widely accepted throughout the middle ages and into the latter half
of the 19th century, because it fitted nicely with the religious views of most people.
Some recipes
Box + Rags + Grain = mice
Meat + warm temperature = maggots
Proof that spontaneous generation is false.
- Mid 1600s: Francesco Redi demonstrated that maggots did not developed from meat if the meat was protected by a fine gauze cover.
- Late 1700s: Lazzaro Spallanzani demonstrated that nothing grew in liquids that were boiled and stored in closed containers. The proponents of spontaneous generation argued that a free supply of air was required for the “vital force” to reach the liquid.
Germ Theory
Ignaz Semelweis (1847)
Showed that puerperal sepsis (childbed fever) is contagious. Medical students were transporting the “cadaveric principles” from the morgue to the clinic. Hand washing in chlorine solution solved the problem.
Germ theory
Joseph Lister (1867)
Reported that death due to infection could be reduced dramatically if diluted phenol was used to soak the medical devices and surgical dressings and to spray the general area during surgery.
Germ theory
Robert Koch (1877 and 1882)
- Published that anthrax was caused by the bacterium Bacillus anthracis.
- Showed that tuberculosis, causing one-seventh of all human deaths at the time, was caused by a bacterium, Mycobacterium tuberculosis.
Germ Theory
Louis Pasteur
- Showed (experiment) that microorganisms were present in the air, a possible source of infection.
- Led to development of effective sterilization procedures and pasteurization.
- Developed vaccines for multiple diseases, such as anthrax, fowl cholera and rabies.
- 1885: first successful administration of a vaccine against rabies.
