Cellular Respiration and Fermentation

These flashcards cover key terms and concepts related to cellular respiration and fermentation, providing definitions and context for better understanding for exam preparation.

Cellular Respiration

The process by which cells convert organic molecules into usable energy (ATP), involving pathways such as glycolysis, the citric acid cycle, and oxidative phosphorylation.

ATP (Adenosine Triphosphate)

The primary energy currency of the cell, used to drive various cellular processes.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing a net yield of 2 ATP and 2 NADH.

Aerobic Respiration

A form of cellular respiration that requires oxygen and produces ATP by using organic molecules and the electron transport chain.

Anaerobic Respiration

A type of respiration that occurs without oxygen, using other electron acceptors and producing less energy than aerobic respiration.

Fermentation

A metabolic process that converts sugars into acids, gases, or alcohol, occurring without oxygen and allowing for the regeneration of NAD+.

Redox Reactions

Chemical reactions that involve the transfer of electrons, where one substance is oxidized (loses electrons) and another is reduced (gains electrons).

Chemiosmosis

The diffusion of hydrogen ions across a membrane through ATP synthase to generate ATP.

Citric Acid Cycle (Krebs Cycle)

A series of enzymatic reactions in the mitochondrial matrix that oxidizes acetyl CoA to CO2, producing ATP, NADH, and FADH2.

Oxidative Phosphorylation

The final stage of cellular respiration where ATP is produced by the electron transport chain and chemiosmosis.

NAD+

A coenzyme that acts as an electron carrier in cellular respiration, becoming NADH when reduced.

FAD

Another coenzyme that accepts electrons and is reduced to form FADH2 during cellular respiration.

Substrate-level Phosphorylation

The direct synthesis of ATP from ADP and a substrate during metabolic reactions, occurring in glycolysis and the citric acid cycle.

Proton-motive Force

The potential energy stored as a result of a hydrogen ion (H+) gradient across a membrane, used to synthesize ATP.

Lactic Acid Fermentation

A type of fermentation where pyruvate is reduced to lactate, occurring in muscle cells and some bacteria.

Alcohol Fermentation

A process in which pyruvate from glycolysis is converted into ethanol and CO2, commonly carried out by yeast.

Electron Transport Chain

A series of protein complexes in the inner mitochondrial membrane that transfer electrons from NADH and FADH2 to O2, driving ATP synthesis.

Acetyl CoA

A key intermediate in metabolism that enters the citric acid cycle, formed from pyruvate.

Organic Molecules

Compounds primarily made of carbon that are the primary source of energy for cellular respiration.

Heat Energy

The energy that is released as a byproduct of cellular respiration when organic molecules are broken down.