Prokaryotes - Bacteria and Archea (week 4) Flashcards
Horizontal Gene Transfer
movement of one or more genes from one species to another
increase genetic diversity, common among archae and bacteria
Prokaryotic Cell Structure
No membrane bound nucleus
Circular DNA plasmid
Reproduction of Prokaryotes
reproduce asexually (means binary fission)
methodes:
Conjugation - sex pilus forms between two cells; donor passes DNA to recipient cell through pilus
Transformation- occurs when bacterium picks up free pieces of DNA from other prokaryotes
Transduction- occurs when bacteriophages carry portions of bacterial DNA from one cell to another (vectors)
Endospore
response to unfavorable conditions
dormant stage
resistant to radiation, disinfectants
Prokaryotic Nutrition
Phototrophs - get energy from light
Chemotrophs - get enrgy from chemical compounds
Autotrophic Prokaryotes
Photoautotophs
some do not produce O2
some use solar energy to produce CO2
photosynthetic
Chemoautotrophs
osidize inorganic compounds to obtain the necessary energy
use it to reduce CO2 to an organic compound
Chemosynthetic
pathogenic Bacteria
Evolving resistance faster than we can develop new drugs
ex. plague, sexual transmitted disease, strep throat, boils, MRSA, Lyme disease, Cholera
Salmonella Outbreaks
group of rod shaped enter bacteria
passed through feces
common sources: pet feces, amphibians, poulty, beef, milk, eggs
E coli outbreaks
resides in intestines
leads to severe stomach cramps, bloody diarrhea and occasionally kidney faliure
Koch Postulates
A test for wether a particular microorganism causes a particular disease
Differences between Archea and Bacteria
base sequence of their rRNA
Archea do not have peptidoglycan their cell walls like the bacteria
Archae biomedically more like Eukarya
Features in eukaryotic nucleus and cytoplasm that suggest common ancestry include
Histone proteins
Ribosomal proteins
RNA polymerase
Archea
many live in harsh conditions
- salty lakes
- hot sulfur springs
