Microbiology By: Rachel Hillard RN
Feb 25, 2016
MicrobiologyBy: Rachel Hillard RN
An advanced biology course Biology is the study of living organisms Microbiology is the study of very small living
organisms called microorganisms or microbes Microbes are ubiquitous
What is Microbiology
Viruses Bacteria Archaeans Certain Algae Protozoa Certain fungi
Types of Microorganisms
Pathogens- disease causing microbes (germs) Only about 3% of microbes
Non-pathogens- do not cause disease and some are beneficial to us.
Classifications of microbes
We have approximately 10 times as many microorganisms as cells living on and in our bodies 10 trillion cells x 10= 100 trillion microbes
500 to 1000 different species of microorganisms live on and in us
Why study Microbiology
Indigenous microflora Opportunistic pathogens Photosynthesis Decomposers or saprophytes Bioremediation (genetic engineering) Microbial ecology Plankton Phytoplankton Zooplankton Digestion Biotechnology
What Microorganisms do
Antibiotics Genetic engineering Cell Models
Microorganisms cause two categories of diseases:1. Infectious disease
1. When a pathogen colonizes the body and subsequently causes disease
2. Causes most illnesses and deaths. 3. The leading cause of death in the world and 3rd
in the US4. 50,000 deaths per day
2. Microbial intoxication 1. Toxin is ingested that has been produced by a
microorganism.
Diseases
Microbiologist Bacteriologist Phycologists Protozoologists Mycologists Birologists
Careers in Microbiology
Agricultural Biotechnology Environmental / bioremediation Medical/ Clinical Microbial Genetics / Genetic Engineering Microbial Physiology Paleomicrobiology Parasitology Sanitary Microbiology Veterinary
Careers in Microbiology
Fossils of primitive microorganisms (as many as 11 different types) were found in ancient rock formations in northwestern Australia dating back to about 3.5 billion years ago.
The earliest molecular fossils date back to between 3.7 and 4 billion years ago.
First microorganisms on earth where possibly archaeans and cyanobacteria
First Microorganisms on Earth
Infectious diseases of humans and animals have possibly existed for as long as humans and animals
Human pathogens have existed for thousands of years as observed in the bones and internal organs of mummies and early human fossils Bacterial diseases such as
Tuberculosis Syphilis Parasitic worm infections
Earliest Known Infectious Diseases
Egypt about 3180 BC. First recorded epidemic
1000 BC Near the end of the Trojan War the Greek army was decimated by an epidemic
thought to have been the bubonic plague. 1500 BC The Ebers papyrus describing epidemic
fevers discovered in a tomb in Thebes Egypt 1122BC in China Disease thought to be smallpox Plagues in
Rome 790, 710, 640 BC Greece 430 BC
Earliest known Pestilence
Rabies Anthrax Dysentery Smallpox Ergotism Botulism Measles Typhoid fever Typhus fever Diphtheria Syphilis
Other Dieseases
From the discovery of the first microorganisms it took about 200 years before a connection was established between microorganisms and infectious diseases.
Significant events in early history Development of microscopes Bacterial staining procedures Microorganisms cultured in the lab
History of Microbiology
Anton van Leeuwenhoek (1632-1723) Father of microbiology/ bacteriology/
protozoology First person to see live bacteria and protozoa Not a trained scientist As a hobby he ground tiny glass lenses and
mounted in small metal frames creating single-lens microscopes or simple microscopes
He examined almost anything he could get his hands onTeeth scrapings water from ditches/ponds blood water soaked from peppercorns sperm diarrheal stools
Pioneers in Microbiology
The tiny living creatures he observed he called “animalcules”
He recorded his observations in the form of letters sent to the Royal Society of London.
For all of his discoveries Leeuwenhoek never associated microbes with the cause of disease.
Leeuwenhoek
Abiogenesis- spontaneous generation Biogenesis
Theories
Louis Pasteur (1822-1895)