Exam 2 Part 3 Flashcards
metabolism
stepwise energy generation
-lot of repurposing and reusing
enzymes control every step
energy production
complete oxidation with wastes CO2, H2O and e- carriers
energy sensing
cell looks at energy level
(measures ATP:AMP)
How much ATP do we have?
substrate-level phosphorylation
direct transfer of phosphate group to ADP
glycolysis
occurs in cytosol
2ATP + 1 glucose -> 2 pyruvate + NADH + 4 ATP
glucose not completely oxidized
glycolysis regulation
by allosteric regulation
-phosphorylate enyme with ATP
destablization of glucose
during glycolysis
phosphorylation of glucose (traps it in cell)
fermentation
regeneration of NAD+
does not completely oxidize pyruvate
yields either lactate or ethanol
lactate
produced by fermentation
MUST get rid of it - or eventual death
cannot ferment with this product indefinitely
mitochondria
site of CAC and electron transport chain product of endosymbiosis -divide by fission (on own) -DNA homologous to Rickettsia -double membrane
mitochondria locations and shape
located in lots of muscles, flagella, overlap with each other in cells
-placed well to provide energy
matrix
innermost part of mitochondria
inner membrane
in mitochondria - invaginate(cristae) in folds for more surface area
super selective - tight control
cristae
invaginations of inner membrane
outer membrane
outer part of mitochondria
very porous - not very selective - almost freely diffusive
inter membrane space
space between the two mitochondrial membranes
acetyl CoA
needed to begin CAC
made from pyruvate
citric acid cycle
in the mitochondria matrix
complete oxidation of glucose
6 C molecule -> 4C molecule + 2CO2 (fully oxidized C) +NADH+FADH2+GTP
O2 NOT involved
CAC products per 1 pyruvate
3 CO2
4 NADH => 3 NADH +1 (pyruvate -> acetyl CoA)
1 FADH2
1 GTP
CAC regulation
pyruvate to acetyl CoA - cycle can’t run without acetyl CoA
CAC and glucose
cycle runs twice for each molecule of glucose because glycolysis produces 2 molecules of pyruvate
CAC and GTP
production of GTP during CAC is substrate level phosphorylation
CAC molecules produced during cycle
molecules produced during can be used for other processes - feeds energy into metabolism
phosphorylated glucose
glycogen -stored for later use
storage in adipose cells
2 fatty acid chains with 1 glucose backbone
more fully reduced and have more energy
B-oxidation cycles needed to chop up fatty acids
C/2 -1
B-oxidation
feeding storage fats into energy generation
B-oxidation product generation
loss of 2 ATP and yield of 1 NADH and 1 FADH2 per cycle
minus 1 FADH2 total with each double bond
NADH from glycolysis proton pumping
6 b/c uses energy to travel into mitochondria
NADH from CAC and B-ox proton pumping
10 protons
FADH2 from CAC and B-ox proton pumping
6 protons
oxidative phosphorylation
uses electrons to generate a gradient to phosphorylate ATP
ATP synthase
enzyme on inner membrane that uses proton gradient to phosphorylate ATP (ox phos)
FADH2 electron transport complexes
II->III-> IV
NADH electron transport complexes
I ->III-> IV
cytochrome
e- carrier between III and IV complex - is the most highly conserved protein
proton motive force
concentration gradient and electropotential carries protons through - REALLY FAVORABLE
ATP synthase conformation
bump on rotator changes the conformation of stator which turns ADP to ATP
proton gradient in mitochondria
needed to help move ATP out of mitochondria
4 protons to make and deliver ATP
