ch 27 bacteria and archaea

prokaryotic cell

no nucleus, no membrane-bound organelles, smaller than eukaryotic cell

spherical/coccus/cocci

2-diplococcus, 3-cocci, 5-streptococcus, grape like cluster-straphylococcus

rod-shape/bacillus/bacilli

3-bacilli, 5/line-streptobacillus

spiral

spirilla(loose coil), spirochete(tight coil)

cell wall

made of amino acids/sugar it provides structure, prevents lysis in hypotonic environments

bacteria

peptidoglycan

archaea

polysaccharids proteins

Gram +

PURPLE

Gram -

PINK

the four steps of staining

Crystal violet, Iodine, Alcohol, Safranin

Capsule

sticky polysaccharide or protein layer, allows prokaryotes to stick to substrate, invisibility to immune system

Endospores

helps prokaryotes survive tough environmental conditions (lack of nutrients/low moisture) will revive when conditions improve

Fimbriae

hair-like appendage that allows it to stick to other cells

Pili (or sex pili)

Allows for 1 way transfer of DNA

Motility

about half of all prokaryotes exhibit taxis-directed movement(coil/spin) Flagellum

Exotoxins

Toxin secreted by bacteria; can cause disease even if bacteria aren’t present

Endotoxin

Source is gram- cell wall when bacteria dies, (lipopolysaccharide layer)

Mutualism

+/+

Commensalism

one gets a benefit one is mutual with it so no benefit or harm

parasitism

one gets a benefit one gets harmed

Some prokaryotes have

specialized membranes that perform metabolic functions (aerobic prokaryotic and photosynthetic prokaryote)

chromosome

singular, circular, contains less genes than eukaryotic chromosomes

plasmids

small rings of DNA; replicate independently of main chromosome

prokaryotes reproduce quickly by

binary fission and can divide every 1-3 hours under optimal condition (rapid reproduction and mutation)

Genetic recombination

combining of DNA from two sources

transformation

cell takes up DNA from environment

Transduction

movement of genes between bacteria by phages

conjugation

genetic material is transferred between prokaryotic cells

F factor

required for pilus formation

R plasmids

carry genes for antibiotic resistance

photo

how they obtain energy/light

autotroph

where carbon source comes from/usually co²

heterotroph

from other organisms

chemo

chemicals

obligate aerobe

must use o2 in metabolism(cellular respiration)

obligate anaerobe

do not use o2 in metabolism, fermentation, anaerobe respiration

facultative anaerobe

can do aerobic or anaerobic metabolism

nitrogen fixation

adding N²

anabaena

fix nitrogen but can’t do photosynthesis, has heterocyst and photosynthetic cells

biofilm

aggregate of microorganisms secret signaling cells

Domain Archaea

ETACK, Euryarchaeota, thaumarchaeota, agarchaeota, crenarcheota, korarchaeota

thermophiles

loves heat

halophiles

love salt

methanogen

produce methane as byproduct of metabolism

protcobacteria

origins of mitochondria

chlamydias

lacks peptidoglycan

spirochetes

spiral through the environment

cyanobacteria

photosynthetic chloroplasts origins (anabaena, oscillatoria)