phototrophs Flashcards
What is required for photosynthesis?
Light-sensitive pigments
are they lots of pigments?
Yes, each with a different absorption spectrum
ex of pigment
- chlorophyll a
- Bacteriochlorophyll a
the cyclopentanone ring?
c sa qui rentre ds la membrane
Reaction center
structures that participate directly in the reactions that lead to energy conservation
Chlorophyll or bacteriochlorophyll
molecules are arranged
in
photocomplexes containing other
photosensitive pigments and proteins
which pigment participate directly in the photosynthesis reaction ?
the pigments in the reaction
center
the pigments that are aroung act as
antennae to harvest light and funnel the energy to the RC
Carotenoids what are they ?
hydrophobic, light –sensitive
pigments
carotenoids are firmly embedded in the ?
photosynthetic membrane
the primary role of carotenoids is?
to protect the system against bright light
why need to protect from the bright light?
may lead to production of toxic forms of
oxygen.
Phycobilins form complexes with proteins that
are the main
light-harvesting systems in
Cyanobacteria:
light-harvesting systems in
Cyanobacteria?
phycobilisomes.
phycobilisomes job?
They harvest
light of other wavelengths than chlorophyll
where to find
phycobilins?
Cyanobacterias
-chloroplast of red algae
in plants and algae where occurs photosynthesis?
Chloroplast
where exactly in the chloroplast?
chlorophylls that are attached to the membrane of the thylakoid
where is generated the pmf in plants and algae ?
generated across the thylakoid membrane.
details?
- Stroma:Alkaline,negative
- Lumen or intrathylakoid space:acidic, positive
photosynthetic pigments are integrated
into internal membranes,where in heliobacteria?
In the cytoplasmic membrane itself
photosynthetic pigments are integrated
into internal membranes,where in purple bacteria
In intracytoplasmic membrane
systems
photosynthetic pigments are integrated
into internal membranes,where in cyanobacteria,prochlorophytes?
In thylakoid membrane
photosynthetic pigments are integrated
into internal membranes,where in green sulfur bacteria and green nonsulfur bacteria
chlorosome
what is a chlorosome
are giant antenna systems
arranged in rod like arrays
in the chlorosome?
Bchl
c, d, e
what is their job BChl c,d,e ?
transfer light energy to Bchil a in the rx center
trough what?
small molecule called FMO protein
what can we find in chlorosome
bacteriochlorophyll molecules
are they attached to proteins?
no they aren’t
It is the best photosystem to capture
energy at very low light intensity
Green bacteria can colonize niches of
very low light intensity,such as?
deep,
anoxic aquatic habitat
