Starting with classification Flashcards
Whats taxonomy?
the science of classifying things
whats phylogeny?
the evolutionary history and line of descent of a species or higher taxonomic group.
WHat was the five kingdoms of life (old) ?
- Hierarchical -the idea of “progression”
- Simpler organisms at the base. Complex organisms at the top.
what was the domains view of life?
- 16S Ribosomal RNA gene (16S rRNA)
- This resolved life into three domains (Archaea, Bacteria, Eukarya).
the current view is….
Based on multiple gene phylogenies.
Still being resolved.
effect of temperature on bacteria depends on…
…habitat
define obligate
it can ONLY grow atthayt specific temperature
define facultative
it CAN grow at that temperature.
all species have a…
minimum, maximum, and optimum temperature.
What are microbes cultured in?
Microbes are grown in a nutritive medium (plural: media)
- Solid agar
- Liquid broth
Growth rates in a nutritive medium….
…vary but can be very rapid.
When culturing microbes…
… media and conditions must be suitable.
Whats a complex media?
precise chemical composition unknown.
E.g. yeast extract, bovine serum albumin.
whats defined media?
composition is chemically defined
whats selective media?
restrict growth to a few microbes
whats differential media?
used to distinguish microbes.
E.g. blood agar for β-haemolytic organisms
How do eukaryotes reproduce?
Eukaryotes may reproduce sexually (meiosis) and divide by mitosis
How do prokaryotes reproduce?
Prokaryotes grow via binary fission.
2 new cells every generation
generation times of binary fission vary by….
… species and conditions.
Bacillus subtilis ~20 mins
Mycobacterium tuberculosis - 16 hours or more
What are the Microbial growth in liquid culture phases?
Lag phase
Exponential (log) phase
Stationary phase
Death phase
Whats an autotroph?
an autotroph is an organism that produces its own food
eg: plants, algae, some bacteria, phytoplankton, and archaea.
Whats a heterotroph?
A heterotroph is an organism that does not make its own food.
eg: animals, fungi, most protozoa, most bacteria.
define photoautotroph?
photosynthetic bacteria (green sulphur, purple sulphur, cyanobacteria), algae
define chemoautotroph?
iron, sulphur, hydrogetna nd nitrifying bacteria. Some Archaeobacteria.
define photoheterotroph?
purple nonsulphur, green nonsulphur
define chemoheterotroph?
plants, animals, fungi, most bacteria.
