Topic 6 Flashcards
characteristics of chemolithotrophy?
only occurs in prokaryotes
evolved when organic molecules weren’t abundant
which primary electron donors does chemolithotrophy use?
H2S, Fe, H2, NH3
what does chemolithotrophy not require?
glycolysis
fermentation
bridge reaction
Krebs cycle
what does chemolithotrophy require?
ETC
oxidative phosphorylation
why aren’t all metabolic pathways equal?
using different primary electron donors or final electron acceptors generate a proton gradient in which can differ in strength
-organic electron acceptors hold more potential energy and generate greater PMF than inorganic
-oxygen is the strongest final electron acceptor and will generate a greater PMF
strength of PMF for aerobic respiration?
greatest PMF—> most ATP
strength of PMF for aerobic respiration?
less PMF—> less ATP
strength of PMF for chemolithotrophy?
least PMF—> least ATP
how do reduction reactions work?
-polar covalent bonds in the reactant are broken
-nonpolar covalent bonds in the products are formed
-bonding electrons between carbon and oxygen in CO2 have moved closer to the C atoms in glucose so CO2 is reduced
-bonding electrons between the oxygen and hydrogen in H2O have moved farther away from the O atoms in O2 so water is oxidized
what are membranes in the chloroplast?
outer
inner
thylakoid
what are the two spaces in the chloroplast?
stroma
lumen
what is the electromagnetic spectrum?
waves of different solar energy exist as photons and can be visible
which part of the electromagnetic spectrum is important in photosynthesis?
400-700
what happens when a photon hits an object?
it can be:
reflected (bounces back)
transmitted (pass through)
absorbed (electrons gain energy of the photon)
what is pigment?
molecules efficient at absorbing photons
how do pigments work?
their chemical structure allows their electrons to absorb solar energy and move to a higher level
-they absorb specific wave lengths which must match exactly the energy needed to raise an electron to a higher level
what do blue pigments do to electrons?
raise them 2 levels
what do green pigments do to electrons?
wont raise an electron
what do red pigments do to electrons?
raise them 1 level
where are photosynthetic pigments?
embedded in the thylakoid membrane