It consists of a series of molecules, most of them proteins called __. First one compound is __, then it is __ as it passes electrons to the next compound, which is __, and so on in a cascade. The electrons move from one compound to another down to the last moeclue, which is __. As the electrons move from one compound to another, they lose energy. All along the way, the __ in the cascade allow energy to be released in small enough amounts to be used by the cell.
cytochromes
reduced
oxidized
reduced
oxygen (final electron acceptor)
redox reactions
The compounds which carry and donate electrons (plus their energy) to the __ are __ and __, produced in __, __, and __.
ETC
NADH
FADH2
glycolysis
linker reaction
Krebs Cycle
Each molecule of NADH can produce __ ATPs.
FADH2 can produce __.
3
2
What is the chemiosmotic theory of ATP synthesis (oxidative phosphorylation)?
energy released as eletrons pass through the ETC is used to pump H+ from the mitochondrial matrix across the inner membrane to the intermembrane space, setting up a H+ concetration gradient
H+ moves back into the matrix in response to its electrochemical gradient, but only at points where there are ATP synthases
WHen NADH donates electrons to the ETC, it is __; this __ needed to keep glycolysis and the Krebs cycle going.
oxidized to NAD+
regenerates the NAD+
Oxidative phosphorylation and the ETC will not occur under what circumstances?
no oxygen being present
Net gain of Oxidative Phos.
28 molecules of ATP from NADH
4 from FADH2
Which molecule has the most energy? least? in between?
glucose most
NADH: 3 ATP
FADH: 2 ATP
ATP least
What is the purpose of fermentation?
to regenerate NAD+ to keep the biochemical pathway of glycolysis going so that the cell gains ATP when no O2 is present
Where does fermentation ccur?
in cytosol follwing glycolysis only if O2 isn't present
Uses __ produced in glycolysis to convert the __ produced in glycolysis to either __ or __.
NADH
pyruvate
lactic acid
alcohol and CO2
Lactic acid:
- produced in __; some microorganisms
- in higher nimals, it is carried by the __ to the __, where it's converted back to __.
animal cells
bloodstream
liver
pyruvate
Alcohol (ethanol) and CO2
produced in __, osme microorganimss
reaction is __.
plants
irreversible
True or False: in fermentation, no atp is produced
true
Net gain of fermentation
2 atp from glycolysis
NAD+
Total ATP formed from substrate-level phosphorylation.
four
Total NADH formed through glycolysis, pyruvate, and CAC
ten
Total FADH2 produced
two (CAC)
ETC yields:
__ ATP/ NADH when produced inside mitochondrion
__ ATP/ NADH when produced outside mitochondrion in glycolyis
__ ATP/ FADH
3
2
2
Total production in aerobic respiration
8 NADH (inside) x 3 ATP/ NADH= 24 ATP
2 NADH (outside mitochondria) x 2 ATP/ NADH= 4 ATP
2 FADH2 x 2 ATP/ FADH2= 4 ATP
Total ATP yield
4+24 (ETC)+ 4 (ETC) + 4 (ETC)= 36
Anaerobic Respiration net yield
two ATP per glucose
Poisons can affect cellular respiration in the ETC. How?
ETC as rotenone binds to one of the electron carriers in first protein complex, preventing electron passage
ETC in third complex: by cyanide and carbon monoxide (block passage to oxygen)
Proteins affect CR through inhibiting __.
ATP synthase
oligomycin blocks passage of H ions
A third poison, called __, makes the membrane of mitochondria __>
