12 - Oxidative Phosphorylation Flashcards

This set of flashcards covers key terms and concepts related to cellular respiration and metabolism, including pyruvate metabolism, the citric acid cycle, the electron transport chain, and the roles of reactive oxygen species.

Pyruvate Transport

The process in which pyruvate moves through the outer and inner mitochondrial membranes to reach the matrix for oxidation.

Mitochondrial Carrier Proteins

Proteins that facilitate the transport of pyruvate across the mitochondrial membranes.

Pyruvate Dehydrogenase Complex (PDC)

An enzyme complex that converts pyruvate into acetyl-CoA while releasing carbon dioxide.

Electrons from Pyruvate Oxidation

Electrons released from pyruvate oxidation are transferred to NAD+, forming NADH.

Citric Acid Cycle (TCA Cycle)

A series of enzymatic reactions that converts acetyl-CoA back to oxaloacetate, producing NADH, FADH2, ATP (or GTP), and CO2.

Acetyl-CoA

A two-carbon molecule that enters the TCA cycle by combining with oxaloacetate.

Electron Transport Chain (ETC)

A series of protein complexes located in the inner mitochondrial membrane that transfers electrons and pumps protons to create a proton gradient.

NADH

The reduced form of NAD+, which carries electrons to the electron transport chain.

Chemiosmosis

The process by which ATP is generated from ADP using the energy from the proton gradient established by the electron transport chain.

ATP Synthase

An enzyme that synthesizes ATP from ADP and inorganic phosphate as protons flow back into the mitochondrial matrix.

Total ATP Yield from Cellular Respiration

Approximately 30-32 ATP molecules can be produced from one glucose molecule.

ADP and AMP Roles

Act as signals for low-energy states; high levels activate PFK-1 to boost glycolysis.

Uncoupling Proteins (UCP)

Proteins that allow protons (H+) to bypass ATP synthase, converting energy into heat instead of ATP.

Reactive Oxygen Species (ROS)

Harmful molecules formed during electron transport that can damage cellular components.

Detoxification Mechanisms

Enzymes like superoxide dismutase (SOD) and catalase modify harmful ROS into less damaging substances.

Implications of ROS

Reactive oxygen species can influence cellular processes, including signaling pathways and immune responses.