Prokaryotes and eukaryotes Flashcards
What do large bacteria do to combat SA: volume diffusion?
Invaginated cell membranes increase SA, large intracellular deposits reduce volume, swim
Mesophilic
15 - 60 degrees, e.g. geothermal hotsprings
Thermophilic
60 - 80 degrees e.g. Yellowstone national park
Hypothermophilic
> 80 degrees - colours due to photosynthetic pigments
DNA thermostability
unstable about 90 degrees - hypothermophiles have a higher G and C content and histone-like proteins. Higher salt concs also help
Halophiles
Tolerance to sale e.g. dead sea - intracellular K+ and glycine
Psychrophiles
Grow at 0 degrees, some metabolically active
Acidophilus and alklophiles
e.g. ferroplasma pH 0 and spirulina pH 10.5
Deinococcus radiodurans
can withstand radiation 3000 higher than would debilitate humans
Morphological classification
Colonies, ultrastructural, staining, cilia, flagella, motility mechanisms, endospores, spores, cellular indusions, colour, cell shape and size
Physiological and metabolic classification
C + N sources, cell was cons, energy sources, luminescence, O relationships, pH, osmotic potential
Ecological classification
Life cycle patterns, symbiotic relationships, disease, habitat preferences
Genetic analysis classification
Transformation, conjugation, plasmids, phage-typing
Molecular classification
Based on 16S RNA genes
Molecular phylogenetics
Nucleotide position = character –> genetic drift and comparisons