Citric Acid Cycle (TCA) Flashcards
Dehydrogenases
main enzymes that make NADH and FADH2
How many reactions is the citric acid cycle?
8
what does the TCA cycle start with?
acetyl coa
What happens to acetyl coa during teh citric acid cycle?
it gets converted to CO2
what hormones rise when you are hungry?
glucagon
epinephrine
cortisol
Where does acetyl-coa come from?
from breaking down glucose, fructose, and galactose
proteins can help make it
can also come from stored fatty acids
also can come from alcohol in liver where it is metabolized
pyruvate enters the ________
mitochondria
do hormones play a role in the regulation of TCA?
no
What are the products of one acetylcoa?
3 NADH
1 FADH
1 GTP
How many molecules of ATP per acetyl coa?
12 ATP
How many ATP does a glucose molecule make during the CITRIC ACID CYCLE
24
does glycolysis occur in all cells?
yes
Why are some cells critically dependent on glycolysis?
because some cells do not have mitochondria and glycolysis is the only way that they can produce ATP
What are some organs that lack mitochondria?
RBC
cornea
lens
regions of retina
what are organs that have very FEW mitochondria?
leukocytes
white muscle fibers
testis
kidney medulla
Where does oxidative phosphorylation occur?
in the inner membrane of mitochondria
what happens during oxidative phosphorylation?
ATP is made by donating electrons to complexes in the membrane of the mitochondria
What is the last electron acceptor in the ETC?
O2
how many ATP does 1 FADH2 make in the ETC
2 ATP
What happens to the ETC with changes in ATP and ADP?
ATP = lots of energy already so ETC slows down bc it does not need to create more
ADP = not a lot of energy so ETC speeds up to compensate and make more energy
What are the main electron donors of oxydative phosphorylation?
NADH & FADH2
How do cells that lack mitochondria or have very few go through glycolysis?
Glucose —> Pyruvate + 2 ATP
I
V
2 Lactate
How many ATP net can be made from one glucose molecule?
38 ATP
BESIDES playing a central role in oxidative metabolism, operation of the TCA Cycle also provides
precursors for biosynthetic pathways like
amino acid, heme & fatty acid synthesis
gluconeogenesis (malate)
metabolic syndrome
a cluster of conditions that occur together, increasing your risk of heart disease, stroke and type 2 diabetes.
