MICRO FINAL Flashcards
7 important parts of microbiology
- microbes and Earth’s History (Biogeochemical cycles) -80% of earth’s history was microbial
- Impact on humans - bubonic plague (black death) 1347 (25mil deaths); potato famine 1846 (10mil plus deaths)
- human microbiome
- plant and animal microbiomes
- food microbiology
- renewable energy - biofuels, bioremediation
- enzyme production - biotechnology; antibiotics
importance of microorganisms
- play a major role in biogeochemical of essential nutrients such as C, N, S etc.
- Cyanobacteria uptake CO2 and produce O2
- production of food products, beverages, antibiotics, bread, cheese, yogurt, and vitamins
- some cause disease in human, plants, and animals
robert hooke
first to describe microbes (fungi) using the microscope
Antoni van Leewenhoek (1632-1723)
first to describe bacteria
Edward Jenner (1796)
vaccinated an 8 year old boy with fluid from cow-pox blisters
Ferdinand Cohn (1828-1898)
discovered endospores
Louis Pasteur (1822-1895)
- discovered that alcoholic fermentation was a biologically mediated process
- developed vaccines for anthrax, chlorea, and rabies
- discovered that living organisms discriminate between optical isomers
- disproved theory of spontaneous generation - led to aseptic technique
Robert Koch (1843-1910)
- demonstrated that microbes cause disease
- developed techniques for obtaining pure cultures of microbes, some still in existence today
limitations of kochs postulates
- Some organisms cannot be grown in pure culture (Treponema pallidum cause syphilis)
- Using humans in completing the postulates is unethical
- Molecular and genetic evidence may replace and overcome these limits (Human papillomavirus cause cervical cancer)
Martinus Beijerinck (1851-1931)
developed enrichment culture technique
– microbes isolated from natural samples in a highly selective fashion by manipulating nutrient and incubation conditions
Sergei Winogradsky (1856-1953)
demonstrated that microbes play a major role in cycling of carbon, nitrogen, sulfur, and oxygen in the environment
–chemolithotrophy = oxidation of inorganic compounds linked to energy conservation
nomenclature of bacteria and archaea
Genus species
– in italics on computer or underlined if you write by hand
Pseudomonas aeruginosa
Bacillus subtilis
Escherichia coli (hand written
Nomenclature of viruses
Order
Family
Genus
Specific Epithet
influenza A virus
Classifications of microbes
cellular: fungi, protists, bacteria, archaea
acellular: viruses, viroids, satellites, prions
classification schemes (of microbes)
three domain system, based on a comparison of rRNA genes, divides microorganisms into :
- bacteria
- archaea
- eukarya
bacteria and archaea structure and function
prokaryotes differ from eukaryotes in size and simplicity
- most prokaryotes lack internal membrane systems
- term prokaryotes is becoming blurred
The Size, Shape, and Arrangement of Bacterial Cells
shape: round or rod shaped
arrangement: clusters (staph)
size: varies
morphology
spherical - rods
rod - bacillus
curved rod - vibrio
spiral - spirillum
stell - star
spirochete
inclusion bodies
storage of organic molecules, metabolic end products, energy building blocks
- glycogen storage
- carbon storage
- amino acids - cyanophycin granules
- phosphate - polyphosphate; atp synthesis, dna/rna, plasma mem.
- sulfur globules