unit 1 micro Flashcards
what are microorganisms
small organisms that require a microscope to view
pathogen is
microorganisms that cause disease
non-pathogenic roles microorganisms play
industrial: biofuels, medicine
food: bread, alcohol, yogurt
symbiotic: normal flora in body
prokaryotic microorganisms include
bacteria & archaea
bacteria is described as
unicellular organisms found in nearly every habitat on earth has diverse metabolism
archaea is described as
unicellular organisms that live in extreme environments
eukaryotic microorganisms include
algae, protozoa, fungi, helminths
algae is described as
plant-like organisms which can be unicellular or multicellular
protozoa is described as
unicellular organisms with diverse metabolisms
fungi is described as
unicellular (yeast) multicellular molds, mushrooms
helminths are described as
multicellular animal parasites
viruses are:
acellular (no cell structure); contains only proteins and genetic material & is neither prokaryotic nor eukaryotic
what is taxonomy
science of classification, description, identification, and naming of living organisms
what are the levels of taxonomy
broad: domain
specific: genus then species
eukaryotic definition of species
2 closely related organisms that can interbreed
prokaryotic definition of species
a population of cells that have similar characteristics
what is the cell theory
cells are the fundamental unit of organisms, includes biogenesis
robert hooke was …
the first scientist to see structures that we now call cells
anton van leeuwenhoek was
the first scientist to see microorganisms, using a microscope that he constructed
spontaneous generation is
the idea that living things arise from non-living things
francesco redi attempted to
disprove spontaneous generation
redi hypothesized that
maggots appeared on meat because flies were able to lay eggs in the meat, allowing the maggots to hatch (he covered jar, preventing flies from laying eggs)
other scientists rebuked that redi had suffocated the vital force which is essential for life, redi repeated experiment with
gauze
the opposition came back suggesting that
spontaneous generation may occur only for microbes
john needham attempted
to prove spontaneous generation
what did john needham do to prove spontaneous generation
poured broth in flask, briefly boiled the broth and then sealed the flask
what were the results of john needhams experiment
microbial growth in the broth
does needhams experiment prove spontaneous generation?
no the flaks were most likely contaminated & the brief boil may have been insufficient
lazzaro spallanzani attempted to
disprove spontaneous generation
Spallanzani’s experiment was and his results were
poured broth in flask, sealed the flask and then boiled the broth & no microbial growth in broth
Louis Pasteur did
disproved spontaneous generation
what did Pasteur create
s-curve neck flask
describe pasteur’s experiment
broth was poured into flask & boiled then cooled
what did the curve of the neck prevent
microbes in the outside air from entering the flask and contaminating the broth
aseptic technique is
a series of techniques used to prevent contamination
biogenesis is
the theory that all cells only come from other cells
robert remak & rudolf virchow did
remak - first published evidence to support this theory
virchow - popularized this theory
germ theory is
is the theory that some microorganisms can cause disease
ignaz semmelweis proposed & implemented
proposed that physicians were transferring the causative agent of puerperal fever to patients
implemented handwashing, but encountered lots of resistance
pasteur provided:
foundation for this theory (germ) when he discovered that microorganisms could cause food to spoil
pasteurization
using mild heat to control microbial growth in food without affecting taste
joseph lister insisted
handwashing and cleanliness during surgery to decrease the incidence of post-surgical wound infections
robert koch
proved that some bacteria can cause disease through work with cattle and anthrax
robert koch proposed
a series of postulates which are used to correlate a specific microbe to a specific disease
vaccination
using a less virulent pathogen to protect against a more virulent pathogen
edward jenner
first vaccination
what did jenner do
infected a healthy young boy with fluid from cowpox lesions… the boy became mildly ill with cowpox, but did not develop smallpox
pasteur developed vaccines against
rabies, cholera
magic bullet
a chemical that can kill a pathogen without affecting the host
paul Ehrlich
came up with concept of magic bullet
screening many compounds, finding salvarsan to treat syphilis
alexander fleming
credited with the discovery of the first antibiotic – penicillin
