Ch. 1: An Invisible World Flashcards
Microorganisms (microbes) are
Very small organisms
Saccharomyces cerevisiae is the scientific name for what microorganism?
- yeast
- makes beer, wine, bread, etc.
Trichuris trichiura is the scientific name for what microorganism?
Borrelia burgdorferi is the scientific name for what microorganism?
- Lyme disease
- infected Otzi the Iceman
Taxonomy
The classification, description, identification & naming of living organisms
Classification
The practice of organizing organisms into different groups based on shared characteristics
The miasma theory
- mal’aria = bad air
- believed by Ancient Greeks & Romans
- disease attributed to bad air
- ancient civilizations developed system to deal w/sewage
Piptoporus betulinus is the scientific name for what microorganism?
- w/Otzi the Iceman’s belongings; believed he was treating health ailments with it
Mycobacterium leprae is the scientific name for what microorganism?
- Leprosy
Hippocrates (460-370 BC) is considered what?
- Father of Western medicine
- believed disease had natural cause from patients or environment
- dismissed theory that disease had supernatural cause
- was a physician
Thucydides (460-395 BC) was considered what?
- Father of Scientific History
- advocated for evidence based analysis of cause & effect reasoning
- made observation during Athenian plague that survivors didn’t get reinfected even when taking care of the sick, which showed understanding of concept of immunity
Marcus Terentius Varo (116-27 BC) was what?
- 1st prolific Roman writer
- 1st to propose concept that things we can’t see cause disease
Antone van Leeuwenhoek (1632-1723)
- Dutch cloth merchant
- 1st to develop lens powerful enough to view microbes in 1675
Louis Pasteur
- French chemist
- showed individual microbe strains have different properties
- demonstrated that fermentation is caused by microbes
- invented pasteurization
- developed vaccines for treatment of diseases such as rabies in animals & humans
pasteurization
a process used to kill microorganisms responsible for spoilage
Robert Koch
- German physician
- 1st to demonstrate connection between a single isolated microbe & a known human disease
- discovered bacteria that causes anthrax, cholera, & tuberculosis
Anthrax is caused by what
Bacillus anthracis
Cholera is caused by what
Vibrio cholera
Tuberculosis is caused by what
Mycobacterium tuberculosis
Carolus Linnaeus
- most famous taxonomist
- Swedish botanist, zoologist, physician
- used binomial nomenclature
Eukaryotes
organisms with membrane bound nuclei in cells
Prokaryotes
organisms without membrane bound nuclei in cells
Tree of Life timeline
- Carolus Linnaeus: only animals & plants (1753)
- Ernest Haeckel: added protists & monera (1866)
- Robert Whittaker: added fungi (1969)
What are the 3 domains?
- Archaea
- Bacteria
- Eukarya
What are the 4 domains in Eukarya?
- Fungi
- Protista
- Plantae
- Animalia
Modern taxonomy relies on what?
Comparing nucleic acids (DNA, RNA) or proteins
Horizontal gene transfer
when a gene of one species is absorbed into another organism’s genome
binomial nomenclature
2 word naming system for identifying organisms by genus & species
Haloquadratum walsbyi
- archaeon
- saltwater habitat
- square cells
Staphylococcus aureus
- gram positive bacterium
- consists of clustered cocci cells
The manuals used as standard references for identifying & classifying prokaryotes
- Bergey’s Manual of Determinitive Bacteriology
- Bergey’s Manual of Systemic Bacteriology
Biochemical tests
used to ID chemicals unique to certain species
serological test
used to ID specific antibodies that will react with proteins found in certain species
DNA & RNA sequencing
can be used to ID a particular bacterial species & for classifying newly discovered species
strains
within 1 species of microorganism there are different subtypes
E. coli O157:H7
- strain of E. coli
- causes abd. cramps & diarrhea
- originates from contaminated water or food (raw veggies, undercooked meat)
size a microbe must be to be seen without microscope
100 micrometers
size of bacterial cell
1 micrometer
size of animal cell
10 micrometers
acellular
not composed of cells
bacteria
- found in every habitat
- cell walls made of peptidoglycan
-determined by general shapes
peptidoglycan
composes bacterial call walls
types of bacteria shapes
- spherical (coccus)
- rod-shaped (bacillus)
- curved (spirillum, spirochete, vibrio)
spherical bacteria shape
coccus
rod-shaped bacteria
bacillus
curved bacteria shape
- spirillum
- spirochete
- vibrio
Archaea
- unicellular
- cell walls composed of pseudopeptidoglycan
- found in nearly every habitat, even extreme environments
pseudopeptidoglycan
composes archaea cell walls
Protists
unicellular eukaryotes
Algae
- plant-like protists
- unicellular or multicellular
- photosynthetic
- important part of many ecosystems
- many consumer products contain ingredients from algae
Agar
gel derived from algae, can be mixed w/various nutrients & used to grow microorganisms in a petri dish
Protozoa
protists that make up backbone of food webs by providing nutrients for other organisms
Giardia lamblia
- intestinal protozoan parasite
- infects humans & other mammals
- causes severe diarrhea
Fungi
- not photosynthetic
- cell walls made of chitin
Candida albicans
- unicellular fungus/yeast
- causes vaginal yeast infection, oral thrush
- eukaryotic organism
- morphology similar to that of coccus bacteria1
Molds
- multicellular
- made up of long filaments that form visible colonies
- play critical role in decomposition of dead plants & animals
- produce disease causing metabolites called mycotoxins
- used to make penicillin
chitin
composes fungi cell walls
mycotoxins
produced by molds & cause disease
penicillin
- made using molds
- most prescribed antibiotic
helminths
- multicellular parasitic worms
- disease involves microscopic eggs & larvae
Dracunculus medinensis
- helminth
- causes dizziness, vomiting, diarrhea, painful ulcers on legs & feet when worm exits skin
- infection occurs after person drinks water containing fleas infected w/larvae
viruses
- acellular
- consists of protein & genetic material (DNA or RNA)
- inert outside of host organism
Microbiology
broad term that encompasses study pf all different types of microorganisms
Bacteriology
study of bacterium
Mycology
study of fungi
Protozoology
study of protozoa
Parasitology
study of helminths & other parasites
Virology
study of viruses
Immunology
study of the immune system
phylogenies
evolutionary relationships of different species of organisms on earth
pathogens
cause disease in humans and other animals
