Chapter 12: Glucose Metabolism Flashcards
what is the ultimate goal of glycolysis?
To convert a 6 carbon glucose into two 3 carbon pyruvate molecules
is glycolysis anabolic or catabolic?
catabolic
glucose gets broken down
what is gluconeogenesis the reverse rxn for?
glycolysis
pyruvates are converted back to glucose
is glucose the only sugar that can undergo glycolysis?
no.
what happens to the pyruvate that gets produced by glycolysis?
gets broken down to acetyl CoA for use in the citric acid cycle
what ultimately happens to the carbons in a sugar that has been catabolized by glycolysis?
they are ultimately converted to CO2 that help produce electron carriers in the citric acid cycle (NADH and QH2)
What is QH2 the abbreviation for?
ubiquinol
what are the names of the two electron carriers that come out of the citric acid cycle and go in to the electron transport chain?
NADH and QH2
what do electron carriers (NADH and QH2) do in the electron transport chain?
establish a PROTON gradient across the mitochondrial membrane
what does the electron transport chain ultimately achieve?
significant ATP production via oxidative phosphorylation
what is acetyl CoA used for?
power the TCA (Krebs, citric acid) cycle
build up of fatty acid
CANNOT be used to make net glucose molecules
what is glycolysis?
the breakdown of glucose by enzymes, releasing energy and pyruvic acid.
How many ATP, pyruvate, and NADH molecules do you get for each glucose molecules that enters the glycolysis?
2 (net!) ATP (4 total)
2 pyruvates
2 NADH
what are the ‘recipe ingredients’ for the glycolysis pathway?
1 glucose
2 NAD+
2 ATP
2 (inorganic) phosphates
what are the products for the glycolysis pathway?
2 ATP
2 pyruvates
2 NADH
which molecule is bigger: glucose or pyruvate?
glucose
pyruvate is like two halves of a glucose
How many of the 10 steps in glycolysis are enzymatically catalyzed?
all ten of them
which 5 steps in glycolysis are the ‘energy investment’ phase?
the former 5 steps
all 5 of these steps must be completed in order to break even on the 2 ATP investment that was made
which 5 steps in glycolysis are the ‘energy payoff’ phase?
the latter 5 steps
this is where you start using high energy intermediates to begin MAKING ATP
When can the NADH (generated during glycolysis) NOT go on to be used for making additional ATP in the electron transport chain?
can’t be used under ANaerobic conditions
what does Dr. Shimko mean when he says that metabolism occurs by ‘compartmentalization’
certain activities occur within certain parts of the cell:
in keeping with ‘compartmentalization’, where does glycolysis occur within the cell?
the cytosol
in keeping with ‘compartmentalization’, where does gluconeogenesis occur within the cell?
the cytosol
what does it mean to say that a process is ‘cytosolic’?
it means the process occurs within the cell cytosol