Ch. 7 - Cellular Respiration and Fermentation Flashcards
when oxygen is used in cellular respiration
aerobic respiration
input of glycolysis
glucose
output of glycolysis
2 pyruvate, 2 ATP, 2 NADH
occurs when an enzyme directly transfers a phosphate from a phosphorylated organic molecule to ADP
substrate-level phosphorylation
inputs of breakdown of pyruvate
2 pyruvate
outputs of breakdown of pyruvate
2 acetyl groups, 2 CO2 molecules, 2 NADH
inputs of citric acid cycle
2 acetyl groups
outputs of citric acid cycle
4 CO2, 2 ATP, 6 NADH, 2 FADH2
inputs of oxidative phosphorylation
6 NADH, 2 FADH2
outputs of oxidative phosphorylation
about 30-34 ATP molecules
projections formed by the invaginations of the inner mitochondrial membrane
cristae
involves the breakdown of glucose, a simple sugar, into two molecules of a compound called pyruvate
glycolysis
phase that raises the free energy of glucose, thereby allowing later reactions to be exergonic
Energy Investment Phase
phase (steps 4–5) breaks the fructose-1,6-bisphosphate, a six-carbon molecule, into two molecules of glyceraldehyde-3-phosphate
Cleavage Phase
phase (steps 6–10) produces four ATP, two NADH, and two molecules of pyruvate. Because two molecules of ATP are used in the energy investment phase, the net yield is two molecules of ATP
Energy Liberation Phase
consists of a group of protein complexes and small organic molecules embedded in the inner mitochondrial membrane
Electron Transport Chain
concentration of H+ is higher outside the mitochondrial matrix than inside and an excess of positive charge exists outside the matrix
H+ electrochemical gradient
an environment that lacks oxygen
anaerobic
one mechanism is to use a substance other than O2 as the final electron acceptor of the electron transport chain
anaerobic respiration
the second approach is to produce ATP via substrate-level phosphorylation only, without any net oxidation of organic molecules
fermentation
enzyme that adds a phosphate group from one molecule to another molecule
kinase
enzyme that changes a molecule into its isomer (same atoms, different structures)
isomerase
enzyme that removes hydrogen atom(s) from the substrate; results in the oxidation of the substrate
dehydrogenase
enzyme that transfers a phosphate group from ATP to fructose; point of no return, cell committed to glycolysis; before this step the sugar products can be used efficiently in the cell in other reactions but after this step this is not true.
phosphofructokinase
