Cellular_Respiration_Flashcards

Fermentation

A process that partially degrades sugars without oxygen.

Cellular respiration

A process that fully breaks down organic fuels using oxygen.

Glycolysis

The process that breaks down glucose into two molecules of pyruvate, producing ATP and NADH.

Pyruvate oxidation

The process where pyruvate is transported into the mitochondria and enters the citric acid cycle.

Chemiosmosis

A process that produces ATP in cellular respiration by creating a proton gradient that drives ATP synthesis.

Redox reaction

A reaction involving the transfer of electrons between molecules; oxidation is the loss of electrons, and reduction is the gain of electrons.

NAD+

A coenzyme that accepts electrons and a proton to become NADH, storing energy for the electron transport chain.

Overall equation for cellular respiration

C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy (ATP).

Net gain from glycolysis

Glycolysis results in a net gain of 2 ATP and produces 2 NADH molecules.

Ancient metabolic pathway

Glycolysis is considered ancient because it does not require oxygen, occurs in the cytosol of all cells, and is used by almost all living organisms.

Energy investment phase

In this phase of glycolysis, 2 ATP are used to destabilize glucose.

Payoff phase of glycolysis

The phase in glycolysis that produces 4 ATP and 2 NADH resulting in a net gain of 2 ATP.

Anaerobic conditions and pyruvate

Under anaerobic conditions, pyruvate undergoes fermentation to regenerate NAD+, producing lactic acid or ethanol.

Citric acid cycle

A cycle that fully oxidizes acetyl-CoA to CO2, producing NADH, FADH2, and ATP (GTP).

Electron transport chain

A series of protein complexes that transfer electrons from NADH and FADH2, driving proton pumping and ATP synthesis.

Oxygen in cellular respiration

Oxygen serves as the final electron acceptor in the electron transport chain, forming water.

Evolutionary significance of glycolysis

Its universality and independence from oxygen suggest it was the ATP-producing pathway in early life forms.