Respiration/Fermentation Mastering Flashcards
Why is ATP required for glycolysis?
ATP makes it easier to break apart glucose into two three-carbon molecules.
Glycolysis literally means
sugar splitting
How many net ATPs can be made from one molecule of glucose in glycolysis?
two
What carbon molecules remain at the end of glycolysis?
pyruvic acid
what is glycolysis also called
Embden-Meyerhof pathway.
what is an alternative way to return electron carriers to their oxidized state.
fermentation
What is the role of pyruvic acid in fermentation?
It takes the electrons from NADH, oxidizing it back into NAD+.
What is the fate of the NAD+ newly regenerated by fermentation?
It returns to glycolysis to pick up more electrons.
what are some acids produced by fermentation
Lactic acid and propionic acid
how many electron carriers are reduced in the Krebs cycle only?
four
What is the function of GTP?
an energy carrier
What is the fate of metabolites during respiration?
They are oxidized completely to carbon dioxide and water
Where would you expect to find electron transport chains in a prokaryote?
along the plasma membrane
which compounds provide electrons to the system?
NADH and FADH2
what does oxygen get reduced to at the end of the electron transport chain?
water
what does the electron transport chain do to the concentration of hydrogen ions (protons)?
The concentration of protons is higher outside the membrane than inside.
The process of generating ATP using a proton gradient is referred to as
chemiosmosis.
Why does FADH2 yield less ATP than NADH?
FADH2 electrons enter the electron transport chain at a lower energy level.
what can be used as a final electron acceptor for aerobic respiration?
molecular oxygen
What is one difference between ubiquinones and cytochromes?
Ubiquinones are not made of protein; cytochromes are.
How does the proton gradient help ATP synthase to make ATP?
Protons move from outside the membrane to inside the membrane.
how would lack of iron affect energy production of a bacterium?
Lack of iron would mean lack of heme, and thus lower amounts of functioning cytochrome proteins. This would mean lower energy yields.
Why does lack of oxygen result in the halt of ATP synthesis?
The chain shuts down and can no longer pump hydrogen ions across the membrane, and the proton gradient cannot be maintained.
Why might some cells uncouple the electron transport chain?
Cells can use the energy from the proton gradient for functions other than producing ATP, such as heat generation.
what does not result in a breakdown of the proton gradient?
uncoupling proteins
what is the difference between aerobic and anaerobic respiration
Aerobic respiration uses oxygen as a final electron acceptor, whereas anaerobic respiration uses an inorganic molecule other than oxygen as the final electron acceptor.
When the phosphate is transferred directly from an organic molecule to ADP in order to produce ATP without an energized membrane, what has occurred?
substrate-level phosphorylation
