Lecture 14 - Ch 13 & 14 - Metabolic Pathways Flashcards
the conversion of light energy to chemical energy
photosynthesis
carry out photosynthesis
phototrophs
Photosynthesis requires light-sensitive pigments called
chlorophylls
Photoautotrophy requires _____ production and _____ reduction
ATP & CO2
Oxidation of H2O produces O2
oxigenic phtotsynthesis
oxygen not produced
anoxygenic photosynthesis
participate directly in the conversion of light energy to ATP
reaction centers
funnel light energy to reaction centers
antenna pigments
accessory pigments that absorb energy to be transferred to the reaction center (found in phototrophic organisms)
carotenoids
organisms that obtain energy from the oxidation of inorganic compounds
chemolithotrophs
chemolithotrophs that require organic carbon as a carbon source
mixotrophs
is Hydrogen Oxidation aerobic or anaerobic?
anaerobic
process where ferrous iron oxidizes to ferric iron
iron oxidation
Two groups of bacteria work in concert to fully oxidize ammonia to nitrate
nitrification
steps to nitrification of ammonia-oxidizing bacteria
ammonia –> NH2OH
steps to nitrification of nitrite-oxidizing bacteria
nitrite (NO2) –> nitrate (NO3)
Fixes CO2 into cellular material for autotrophic growth
calvin cycle
in the calvin cycle, ___ molecules of CO2 are required to make 1 molecule of glucose
6
coordinates regulation of genes essential to nitrogen fixation
nif regulon
______ and ______ are the two main regulatory effectors of nitrogen fixation
Oxygen & ammonia
what are the Two mechanisms for catabolism of organic compounds
respiration and fermentation
Exogenous electron acceptors are present to accept electrons generated from the oxidation of electron donors
respiration
Electron donor and acceptor are the same compound
fermentation
A process whereby two or more microbes cooperate to degrade a substance neither can degrade alone
syntrophy
H2 production by one partner is linked to H2 consumption by the other
interspecies hydrogen transfer
what are the most common electron acceptors in anaerobic respiration
inorganic nitrogen compounds
the process of nitrate reduction
denitrification
what is the state of the product of denitrification?
gas
_____ and ______________ are common substrates for chemoorganotrophs
Sugars & polysaccharides
Fatty acids are oxidized by _______
beta-oxidation
Oxidation of ammonia to nitrate
Nitrification
Nitrogen fixation is catalyzed by ______
nitrogenase
