Prokaryote shape
Spehres (cocci), rods (bacilli) and spirals
Hypotonic
when water enters the cell faster than it leaves and cell will swell and lyse like an overfilled water balloon
hypertonic
lose water and shrink away from their wall (plasmolyze) like other walled cells- In hibits the reproduction of prokaryotes
Prokaryotic Cell wall
maintains cell shape, physical protection, and prevents the cell from bursting
Peptidoglycan
a network or modified sugar polymers cross linked by short polypeptides (cell walls contain this)
Gram stain
technique scientists can classify man bacterial species into two groups based on differences in cell wall composition
Gram Positive
bacteria have a simpler cell wall with a large amount of peptidoglycan
gram negative
more threatening; bacteria have less peptidoglycan and it is located ina laer between the plasma membrane and an outer membrane (lipopolysaccharides)
capsule
a sticky layer of polysaccharide or protein- able to adhere to their substrate
fimbriae
a short hair like prokaryotic appendage that functions in adherence to the substrate or to other cells
pili
a long hair like prokaryotic appendage that functions in adherence of in the transfer of DNA during conjugation
taxis
(to arrange) movement toward or away from a stimulus
Nucleoid Region
Where the prokaryotic chromosome is located
plasmids
a small ring of DNA that carries acesory genes separate from those of a bacterial chromosome
binary fission
prokaryotes way of reproducing quickly and in a favorable environment
endospores
a thick coated resistant cell produced within a bacterial cell exposed to harsh conditions
horizontal gene transfer
a process where organisms swap genes with neighboring organisms and without producing offpsring
Photoautotrophs
organisms that capture light energy and use it to drive the synthesis of organic compounds from CO2 (cyanbobacteria, plants, certain protists)
chemoautrotroph
also need only CO2 as a carbon source. however, instead of using light for energy, they oxidize inorganic substances such as (h2s, NH3, Fe2+) ex-Certain prokaryotes
Photoheterotrophs
use light for energy but must obtain their carbon in organic form- a # of marine prokaryotes use this mode
chemoheterotroph
must consume organic molecules for both energy and carbon- found widely among prokaryotes as well as protists, fungi, animals and even some parisitic plants
Obligate aerobes
use oxygen for cellular respiratio and can't grow without it
facultative anaerobes
use oxygen if it is present but can also grow by fermentation in an anaerobic environment
Obligate anaerobes
poisioned by oxygen, some live exclusively by fermentation
anaerobic respiration
in which asunstances other than oxygen such as nitrate ions or sulfate ions accept electrons at the "down hill" end of electron transport chain
fermentation
a catabolic process taht makes a limited amount of ATP from glucose without an electron trasnport chain and taht produces a characteristic end product such as ethyl alcohol or lactic acid
Nitrogen Fixation
prokaryotes convert N2 to NH3, making atmospheric nitrogen availabe to themselves (and eventually to other organisms) for incorporation into organic molecules
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heterocytes
specialized cell that carries out only nitrogen fixation
biofilms
a surface coating colony of prokaryotic that engage in metabolic cooperation
bacteria
one of the two prokaryotic domains, the other being archaea
archaea
one of two prokaryotic domains, the other being bacteria
Extremophiles
(lovers) of extreme conditions in which a few other organisms can survive
extreme thermophiles
(hot) thrive in very HOT environments
extreme halophiles
(salt) line in highly saline enivornments; form a purple red scum that owes its color to bacterior hodopsin
Methanogens
unique way they get energy: use Co2 to oxidize H2, relasing methane as a waste product
Euryarchaeota
(broad) includes the extreme halophiles, and methanogens in this clade
crenarchaeota
(springs as in hydro thermal springs) most extreme thermophiles are in this clade
genetic prospecting
sampling genetic material directly from the environment
korarchaeota
(young man) archaea that don't appear to belong to either Eurya, or Cren so they go in that clade
Nanoarchaeota
(dwarf) genome of a tiny archaean only 500,000 base pairs
decomposer
breaking down corpses, dead vegetation and waste products, thereby unlocking supplies of carbon, nitrogen and other elements
Metabolic Cooperation
certain species of prokaryotes have beneficial associations with other prokaryotes
Symbiosis
(living together) an ecological relationship between organisms of different species that are indirect contact
host
if one symbiotic organism is much larger than the other
symbiot
the smaller of the host
Mutualism
(good) both benefit
commensalism
(medium) organism benefits while neither harming nor helping the other in any significant way
parasitism
(bad) one parasite benefits at the expense of the host
exotoxins
toxin released from gram-positive and gram-negative bacteria
endotoxin
are lipopolysaccharide componets of the outer membrane of gram-negative bacteria, released when the bacteria die and their cell walls break down
bioremediation
the use of organisms to remove pollutants from soil, air or water
Proteobacteria
gram-negative bacteria including photoautotrophs, chemoautotrophs, and heterotrophs. Some anaerboic, some aerobic
Chlamydias
parasites that can only survive within animal cells, gram negative
spirochetes
helical heterotrophs spiral through environment
Gram-Positive bacteria
Bacteria that have a thick peptido glycan cell wall, and no outer membrane. They stain very darkly (purple) in Gram stain.
cyanobacteria
photoautotrophs that are the only prokaryotes with plantlike, oxygen-generating photosynthesis