Document 15621223

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One main chromosome, circular in shape.
Many satellite rings of DNA called plasmids.
Prokaryotes do not have any
membrane-bound organelles.
All of these.
None of these are found in
eukaryotic cells.
Mitochondria
And
Chloroplasts
A small prokaryote with the ability to
make its own food (chloroplasts) or use
oxygen to efficiently metabolize food
(mitochondria) was engulfed by a
larger prokaryote and they lived
happily ever after (symbiotically).
Prokaryotic cells do not have added
surface area in the form of membranebound organelles.
Their surface area (cell membrane or
supply of nutrients) grows by the
square of length while their volume
(metabolic demand) grows by the cube.
They get DNA from other sources:
Transformation (taking in naked DNA)
Transduction (delivered by viruses)
Conjugation (other bacteria thru sex pili)
Generation time 20 min.(ideal)
Haploid (no “hidden” traits)
Share beneficial traits by conjugation.
Decomposers: Recycle building blocks,
Nitrogen-fixing bacteria,
Biotechnology (plasmids +
bio-factories)
Rod-shaped: bacillus
Spherical: coccus
Spiral: spirilla
E. coli, Anthrax, Whooping Cough,
Pink Eye, Salmonella, Typhoid Fever,
Pneumonia, Plague.
Gonorrhea (pairs),
Streptococcus (chains):
Strep Throat, Scarlet Fever, Meningitis
Staphylococcus aureus (clusters)
Staph Infection: most common cause
of skin infection, MRSA is serious.
Lyme disease, cholera, syphilis
Coccus (Streptococcus-chains)
Spirilla (syphilis)
Bacillus (E. coli)
Coccus:
Staphylococcus (clusters)
antibiotics
penicillin
Fungi (molds) make natural
antibiotics for their own defense
against bacterial infection.
Heterotrophic (grazers),
anaerobic (fermenters),
prokaryotes (bacteria).
Photosynthesis/produced oxygen
Endospores
Bacteriorhodopsin
Yes
Their plasma membrane.
The plasma membrane
Into the cell where ATP is
synthesized and used by the cell.
Bacteriorhodopsin
-Halobacteria (salt-loving)
-Archaea bacteria
-mechanism markedly different
and simpler than chl.a.
-photoactive enzyme
-Each photon pumps one H+
out of cell
-7 helices (green) with Retinal
(blue) at center
-Photon changes Retinal from
cis- to trans-configuration
-Moves the H+ across
membrane and out of the cell
Animation: Garland Science
Transforming Light into Chemical
Energy using Bacteriorhodopsin
Cell Animation: bR, ATPsynthase,
flagellum
Owens Lake, CA
Graph I
Since BRP already occupied the green absorption
niche, other pigments would have to evolve using
available wavelengths for energy resulting in
chlorophyll a’s absorption spectrum.
End of Bacteria Review
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