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)