Flashcards in Cellular Respiration Deck (57)
Organisms store glucose as...
Glycogen or starch.
In cells, glucose is oxidized by...
A long series of redox reactions. The released free energy is used to synthesize ATP. Known as cellular respiration.
4 processes of cellular respiration
Glycolysis, pyruvate processing, citric acid cycle, and electron transport/oxidative phosphorylation.
Sequence of enzyme catalyzed reaction by which glucose is converted into pyruvate.
What are the 4 enzymes in the 4 steps of the glycolysis prep phase?
Hexokinase, phosphohexose isomerase, phosphofructokinase-1, and aldolase.
What is produced at the end of the prep phase in glycolysis?
Glyceraldehyde 3-phosphate, dihydroxyacetone phosphate, and 2 ADP.
What are the 6 enzymes in the 6 steps of the glycolysis payoff phase?
Triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, phosphoglycerate kinase, phosphoglycerate kinase, phosphoglycerate mutase, enolase, and pyruvate kinase.
What is produced at the end of glycolysis?
2 pyruvate, 2 NADH, 2 H, 2 H2O and 2 ATP.
Effectively lowers the concentration of the reaction product, drives reaction towards ATP formation.
How is glycolysis regulated?
Feedback inhibition. High levels of ATP inhibit the third enzyme, phosphofructokinase.
What happens to phosphofructokinase when there is too much ATP?
Phosphofructokinase has two binding sites for ATP; when ATP binds the the active site the reaction continues, when ATP levels are too high, it will bind the regulatory site and inhibits the enzyme
Occurs when ATP is produced by the enzyme-catalyzed transfer of a phosphate group from an intermediate substrate to ADP. How ATP is produced in glycolysis and the citric acid cycle.
What is used in glycolysis (consumed)?
1 glucose, 2 ATP, 2 NAD+
What is produced in glycolysis?
2 pyruvate, 4 ATP, 2 NADH
Net amount of ATP production at the end of glycolysis
Fates of pyruvate
Anaerobic conditions (fermentation) or aerobic conditions (citric acid cycle).
Extensions of the inner mitochondrial membrane.
Inside the inner mitochondrial membrane.
Where does pyruvate processing take place?
Enzyme complex called pyruvate dehydrogenase in mitochondrial matrix (eukaryotes).
What are the series of reactions that pyruvate undergoes?
One of its carbon's is oxidized to CO2, NADH is produced, and the remaining two carbon unit is attached to coenzyme A producing acetyl CoA.
What does thiamine deficiency result in
In sufficient pyruvate dehydrogenase activity.
What are the 8 enzymes of the citric acid cycle?
Citrate synthase, aconitase, isocitrate dehydrogenase, alpha ketongluatarate dehydrogenase, succinyl-coA sythetase, succinate dehyrdogenase, fumarase, malate dehydrogenase
What is the net results of the citric acid cycle?
2 CO2, 3 NADH, FADH2, GTP, CoA, 3 H+
Relates to both catabolism and anabolism.
Glucose is completely oxidized to CO2 by...
Glycolysis, pyruvate processing, and the citric acid cycle
As glucose is oxidized, free energy becomes...
For each molecule of glucose that is oxidized, the cell produces...
6 CO2, 4 ATP, 10 NADH, and 2 FADH2.
What happens to the reduced electron carriers after glucose oxidation?
NAD+ is a reduced electron carrier in glucose oxidiation because it is used to accept the electrons. FADH is used as well. NADH and FADH2 (the reduced form) moved to the electron transport chain donates a pair of electrons. Electrons are ultimately transferred to oxygen to form water.
Where do NADH and FADH2 get oxidized?
In the inner membrane of the mitochondria, the electron transport chain.