Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
|
Name the 6 classes of Microorganisms
|
Bacteria
Archaea Fungi (yeasts and molds) Protozoa Algae Viruses |
|
|
Name a microorganism that uses photosynthesis
|
algea
|
|
|
Name the scientist that disproved spontaneous generation.
|
Louis Pasteur
|
|
|
Characteristics of bacteria
|
Single celled organisms
Shapes include rod, coccus (round) and spiral Lack a nuclear membrane Reproduce by binary fission Cell walls composed of peptidoglycan Classified as prokaryotes |
|
|
Prokaryotes
|
Cell whose genetic material is not enclosed in a nuclear membrane.
|
|
|
Characteristics of Archaea
|
Prokaryote
Have cell walls not composed of peptidoglycan Often found in extreme environments Methanogens- produce methane Extreme halophiles- live in high salt environments (such as dead sea) Extreme thermophiles- live at extremely high temperatures (such as hot springs) |
|
|
Characteristics of Fungi
|
Eukaryotes- Cells have a distinct nucleus containing their genetic material (DNA)
May be unicellular or multicellular Fungi have cell walls composed mostly of chitin Unicellular fungi are called yeast Multicellular fungi are molds Fungi can reproduce sexually or asexually They obtain nourishment by absorbing solutions of organic material from their environment |
|
|
Characteristics of protozoa
|
Unicellular
Eukaryotic Move by pseudopods, flagella or cilia Can be free-living or parasites Engulf their nutrients Can reproduce sexually or asexually |
|
|
Characteristics of Algae
|
Eukaryotic
Photosynthetic Algae need light water and carbon dioxide for growth (do not require nutrients form the environment) Use both sexual and asexual reproduction |
|
|
Characteristics of viruses
|
Not cellular (acellular)
Core made of one type of nucleic acid (either DNA or RNA) The core is encased in a protein coat (capsid) This coat is sometimes enclosed in a lipid membrane called an envelope Viruses can only reproduce by using the cellular machinery of living organisms |
|
|
Living characteristics of viruses
|
a. They reproduce at a fantastic rate, but only in living host cells.
b. They can mutate. c. They are made up of the same macromolecules (proteins, DNA or RNA) as living cells d. People constantly talk about killing viruses; but how can you kill something that is not alive? (example: lysol kills 99.9% of viruses and bacteria) |
|
|
Nonliving characteristics of viruses
|
a. They are acellular, that is, they contain no cytoplasm or cellular organelles.
b. They carry out no metabolism on their own and must replicate using the host cell's metabolic machinery. In other words, viruses don't grow and divide. Instead, new viral components are synthesized and assembled within the infected host cell. c. The vast majority of viruses possess either DNA or RNA but not both. |
|
|
Naming and classifying microorganisms
|
1735 Carolus Linnaeus developed the scientific nomenclature (still used today) that assigns each organism two names
Genus Italicized and capitalized Species Italicized but not capitalized Staphylococcus aureus Eschericia coli |
|
|
Robert Hooke
|
1665 using a crude microscope looked at cross-sections of cork, discovered and named ‘cells’
|
|
|
1673-1723 Van Leeuwenhoek- (pronounced 'Laywenhook')
|
was the first to observe bacteria through the lenses of more than 400 microscopes he constructed
|
|
|
1673-1723 Van Leeuwenhoek- (pronounced 'Laywenhook')
|
was the first to observe bacteria through the lenses of more than 400 microscopes he constructed
|
|
|
Spontaneous generation-
|
The belief that life could arise spontaneously from nonliving matter
|
|
|
Biogenesis-
|
states that living cells can arise only from preexisting living cells
|
|
|
1745 John Needham-
|
Boiled nutrient broth before pouring it into covered containers and found it was soon full of microorganisms (thought he had shown spontaneous generation)
|
|
|
1765 Lazzaro Spallanzani-
|
Showed that nutrient broth heated after being sealed in the flasks did not develop microbial growth
|
|
|
1861 Louis Pasteur-
|
Heated long neck flasks with the necks bent into s-shaped curves these flasks showed no signs of life (disproved spontaneous generation)
|
|
|
1860 Joseph Lister-
|
aseptic surgery
|
|
|
1876 Robert Koch-
|
First evidence that bacteria cause disease
|
|
|
Koch’s Postulates-
|
Same pathogen is present in every infected organism
Pathogen must be isolated from host and be grown in culture Pathogen from culture must infect healthy organism Pathogen must be re-isolated from inoculated organism and shown to be the same as the original organism |
|
|
1798 Edward Jenner-
|
Smallpox vaccination, used scrapings from cows (cowpox) to generate immunity in humans
|
|
|
1880’s Pasteur- rabies,
|
cholera vaccines
|
|
|
1910 Paul Ehrlich-
|
salvarsan, treat syphilis, first synthetic drug, (chemotherapy –treatment of diseases with chemical substances)
|
|
|
1928 Alexander Fleming-
|
penicillin, antibiotic, not marketed as drug until 1941
|
