Lc. 7 Cellular Respiration (Metabolism) Flashcards
(16 cards)
What do living cells require for energy?
Living cells require energy from outside sources.
Can food be used directly by cells?
Food is consumed but can’t be used directly.
What must chemical energy from food be converted to?
Chemical energy stored in organic molecules must be converted to ATP.
What happens during a spontaneous redox reaction?
A redox reaction that moves electrons from a less to a more electronegative atom will release energy.
Why must glucose oxidation be gradual?
Glucose contains too much energy to release at once, so oxidation must be gradual.
How does cellular respiration control energy release?
Cellular respiration controls the release and transfer of energy through redox reactions and creating an electrochemical gradient.
What is the role of electron carriers in cellular respiration?
Loss and gain of electrons in cellular respiration is mediated by electron carriers like NAD+ and FAD+.
What is the first stage of harvesting energy from glucose?
The first stage is Glycolysis, which yields 2 molecules of pyruvate.
What happens during pyruvate oxidation?
Pyruvate enters the mitochondrion and is converted to acetyl CoA before the citric acid cycle begins.
What does the citric acid cycle accomplish?
The citric acid cycle completes the breakdown of glucose to CO2.
What is produced by the citric acid cycle?
The cycle produces NADH and FADH2, which relay electrons to the electron transport chain.
What is oxidative phosphorylation?
Oxidative phosphorylation couples electron transport to ATP synthesis.
What is the role of the electron transport chain?
The electron transport chain is composed of multiprotein complexes that alternate between reduced and oxidized states.
What is the final electron acceptor in the electron transport chain?
O2 is the final electron acceptor, forming H2O.
What is chemiosmosis?
Chemiosmosis is the use of energy in a H+ gradient to drive cellular work.
What are the two ways to make ATP?
There is substrate-level phosphorylation and oxidative phosphorylation.
