Prokaryotes Flashcards
Microbiome
any number of existing organisms that exist within that environment
Properties of a prokaryotic cell wall
- maintains shape
- physically protects cell
- prevents cell from bursting in hypotonic event
Capsule
polysaccharide/protein layer that covers many prokaryotes
Endospores
found on some species to endure harsh conditions (ex. dehydration)
Fimbriae
short protein appendages that extend from bacterial cell surface, allowing bacteria to adhere to surface
Taxis
ability to move toward/away from certain stimulus
Chemotaxis
movement of an organism in response to chemicals
Phototaxis
movement of an organism in response to light
Prokaryotes genetic variability can be attributed to …
- rapid reproduction
- mutation
- genetic recombination
Prokaryotes can reproduce within __min to ___ hours
20m-1.3hr
_________ accumulate rapidly in a population due to _____ ___________
Mutation; rapid reproduction;
Transformation
Cell can take up/incorporate foreign DNA from surrounding environment
Transduction
movement of genes between bacteria by bacteriophages
Bacteriophages
viruses that infect bacteria
Conjugation
temporary union of two bacteria for the exchange of genetic materil
What three processes allow for prokaryotic genetic recombination?
- Transformation
- Transduction
- Conjugation
Sex Pili
hair-like surface structures associated with conjugation
F factor
a circular plasmid that so required for the production of sex pili
The F Factor is transferrable during (transfomation/transduction/conjugation)
Conjugation
Cells with F factor are (donors/recipients)
donors
Cells without F factor are (donors/recipients)
recipients
R plasmids
carry genes for antibiotic resistance
Phototrophs
obtain energy from light
Chemotrophs
obtain energy from chemicals
Autotrophs
require CO2 as a carbon source (inorganic)
Heterotrophs
require organic nutrients to make organic compounds
Photoautotrophs
obtain energy from light, and carbon from CO2
Chemoautotrophs
obtain energy from inorganic chemicals, and carbon from CO2
Photoheterotrophs
obtain energy from light, and carbon from organic compounds
Chemoheterotrophs
obtain both energy and carbon from organic compounds
Obligate aerobes
require O2 for cellular respiration
Obligate anaerobes
poisoned by O2, and use fermentation instead (anaerobic respiration)
Faculative anaerobes
can survive with or without O2
Heterocysts
photosynthetic cells and nitrogen-fixing cells exchanging metabolic products found in Anabaena
Nitrogen Fixation
conversion of atmospheric nitrogen to ammonia (N2–>NH3)
Biofilm
surface coating colonies of multiple prokaryotic species
_________otrophic prokaryotes function as decomposers
chemoheterotrophic
Nitrogen fixing prokaryotes can increase availability of…
- Nitrogen
- Potassium
- Phosphorus
Symbiosis
an ecological relationship between two+ organisms
Mutualism
both organisms benefit from the relationship
Commensalism
one organism benefits, while the other isn’t harmed/helped
Parasitism
one organism (parasite) benefits, while the other (host) is harmed
Pathogens
parasites that cause diseases
Exotocins
Toxins released by cell when they are alive, and can cause disease even if prokaryotes that produce them aren’t present
Endotoxins
Toxins released only when bacteria die and their cell walls break down
Bioremediation
use of organisms (prokaryotes) to remove pollutants from environment
Bioremediation can assist in …
- Recovery of metal from ores
- Synthesis of vitamins
- Production of antibiotics
- Production of hormones
