PYRUVATE OXIDATION & KREBS CYCLE Flashcards
Cells use ____ reactions to transfer energy from one substance to another substance
Redox (oxidation & reduction)
Oxidation
The loss of one or more electrons and/or H atoms from a substance
-Reduces energy content
Reduction
The gain of one or more electrons and/or H atoms by a substance
-Increases energy content
Redox reactions
Enable cells to use the energy in food molecules to synthesize energy rich ATP, FADH2, GTP, NADH molecules
Cellular respiration transfers energy rich electrons + H atoms from food molecules to cellular molecules to ____ them to a more _____ rich form
Reduce them to a more energy rich form
Cells use the reduced, energy rich, form of these molecules to-
-Energize endergonic reactions including biosynthetic anabolic reactions
-Make more ATP molecules (FADH2, GTP, NADH)
Most ATP synthesis occurs in the _______ during cellular respiration
Mitochondrion
-Each membrane and each internal compartment performs one or more catabolic processes
Where does pyruvate oxidation & the krebs cycle occur?
The matrix of the mitochondrion
Where does the ETC occur?
The inner membrane of the mitochondrion
Pyruvate oxidation occurs in the ______ ______ when O2 is available
Mitochondrion matrix
When pyruvate is imported into the mitochondrion-
It enters pyruvate oxidation
When pyruvate is imported into the mitochondrion, its enzymes produce the energy rich-
-Acetyl Coenzyme A (Acetyl CoA) molecule
-NADH molecule
Acetyl CoA will be catabolized by the ______ ______ to make what molecules?
-Krebs cycle
-FADH2, GTP, NADH
NADH will be used to make-
ATP
During pyruvate oxidation, pyruvate catabolism generates ___ CO2 molecule as a ____ product
One CO2 molecule as a waste product
CO2 molecules diffuse out of the ____, out of the cell, and enter the bloodstream for delivery to the lungs
Mitochondrion
CO2 molecules exit the body during exhalation, which prevents-
Toxic CO2 accumulation
Pyruvate oxidation enzymes require:
Vitamin B cofactors (B1, B3, B5, B2)
The krebs cycle occurs in the-
Mitochondrion matrix
The sequence of ___ enzymatic reactions releases energy from the energy rich ___ ___ molecules produced by ________ _________
-8
-Acetyl CoA
-Pyruvate oxidation
The krebs cycle produces ___ types of energy rich molecules-
3
-FADH2
-GTP
-NADH
The krebs cycle produces ___ CO2 molecules from _____ ___ as metabolic waste products
-2 CO2 from acetyl CoA
Cells use the energy rich products of the krebs cycle to make ____ molecules
ATP
-1 NADH = ~2.5-3 ATP
-1 FADH2 = ~1.5-2 ATP
-Nucleoside-Diphosphate kinase converts 1 GTP to 1 ATP
Catabolic and anabolic processes ______ molecules
Exchange
-Your cells use some substrates of the krebs cycle and glycolysis to make amino acids, carbs, lipids, nucleotides
