biodiversity Flashcards
what are the domains
arachea bacteria and eukaryota
features of LUCA
dna rna proteins carbs ribosomes lipid bilayer atp
chemiosmotic hypothesis
proteins within ht elipid bilayer pump protons across the membrane to crate an electrochemical gradient which acts as a store of energy
the flow of the protons provides energy to make ATP by ATPas
requires reductants
what are chemoautotrophs
use chemicals from their environment as reductants
equation for methanogenesis
co2 + 8e- + 8H+ to ch4 + 2H20
how did photosynthesis evolve
archaea andbacteria began to diverge
chemical energy and thermal energy was running out
used sunlight
archaen photosynthesis
eg halobacterium salinarium uses bacteriorhodopsin which contains retinal a light absorbing pigment. has two forms which can change orientation and transfer a proton across the membrane
bacterial photosynthesis
uses bacteriochlorophyll
has reaction centres made up of two proteins and a piar of chlorophyll molecules
the chlorophyll molecules absorb light and transfer electrons
has type I and type 11 reaction centres which evolved in different lineages
cyanobacteria
are blue green algae
they contain both type I and type II reaction centres
this is due to lateral gene transfer
turned water into oxygen
oxygen crisis
lots of chemicals in the air reacted with the oxygen made from cyanobacteria
iron oxidised to rust
methane used the o2 to turn into co2 and this cooled the environment
huronian ice age
eukaryotes
are more closely related to archaea than bacteria
symbiosis
persisten tliving together of organisms in close proximity
commensal
one organism benefits the other is unaffected
mutualistci
both benefit
endosymbiosis
one organism lives inside of another
organelles communicate to nucleus via retrograde signalling
