Topic 2: Prokaryotes Flashcards
What domains contain prokaryotes?
Bacteria & archaea
What are the components of prokaryotes?
plasma membrane
cytoplasm
ribosomes
NO membrane bound organelles
How do prokaryotes undergo cellular respiration without a mitochondria?
they use fermentation or aerobic respiration through plasma membrane
What is peptidoglycan?
a carbohydrate polymer in cell wall
this is a characteristic of BACTERIA only
What does the gram stain process tell us?
what the cell wall in the bacterial cell contain
What is the process of gram staining?
- stain with crystal violet dye (purple) & iodine
- rinse with alcohol
- stain with safranin dye (pink)
What does a gram positive bacteria look like?
stains purple
thick wall - primarily peptidoglycan
crystal violet retained & masks safranin
What does a gram negative bacteria look like?
stains pink
thin peptidoglycan layer
crystal violet rinses out, safranin visible
contains lipopolysaccharide outer layer so harder to treat & more dangerous
positive taxis move…
towards stimulus
negative taxis move…
away from stimulus
What are the 3 recombination mechanisms & what happens during each?
- Transformation - prokaryotic cell takes up DNA from foreign environment
- Transduction - phages transfer prokaryotic genes from one cell to another
- Conjugation - direct transfer of genetic material from one cell to another
What are the 4 major nutritional modes? the 2 for autotrophs? the 2 for heterotrophs? energy source carbon source
autotrophs
- photoautotrophs: light energy source; CO2 carbon source
- chemoautotrophs: inorganic chemicals; CO2 carbon source (unique to certain prokaryotes)
heterotrophs
- photoheterotrophs: light energy source; organic compounds (unique to certain aquatic & salt loving prokaryotes)
- chemoheterotrophs: organic compounds; organic compounds
Where did mitochondria evolve from?
endosymbiosis of proteobacteria
Where did chloroplasts evolve from?
endosymbiosis of cyanobacteria
