Cellular Respiration and Energy Harvesting in Cells

Autotrophs

Organisms that produce their own organic molecules.

Heterotrophs

Organisms that obtain organic molecules from others.

Cellular Respiration

Biochemical reactions oxidizing glucose to release energy.

Dehydrogenations

Reactions removing protons during oxidation processes.

Redox Reactions

Reactions transferring electrons and energy between molecules.

NAD+

Electron carrier accepting 2 electrons and 1 proton.

Aerobic Respiration

Respiration using oxygen as the final electron acceptor.

Fermentation

Anaerobic process using organic molecules as electron acceptors.

Anaerobic Respiration

Respiration using inorganic molecules other than oxygen.

ATP

Energy currency of the cell, drives cellular work.

Substrate-Level Phosphorylation

Direct transfer of phosphate to ADP to form ATP.

Oxidative Phosphorylation

ATP production via electron transport and chemiosmosis.

Glycolysis

10-step pathway converting glucose to pyruvate.

Pyruvate Oxidation

Conversion of pyruvate to acetyl-CoA in mitochondria.

Citric Acid Cycle

Cycle oxidizing acetyl-CoA, producing CO2 and energy carriers.

Electron Transport Chain

Series of complexes transferring electrons to create a gradient.

Chemiosmosis

Proton gradient drives ATP synthesis via ATP synthase.

Feedback Inhibition

Regulatory mechanism where end product inhibits pathway.

NADH Recycling

Process regenerating NAD+ for glycolysis to continue.

Energy Yield of Respiration

Approx. 30 ATP produced per glucose in eukaryotes.

Slow-Twitch Muscle Fibers

Aerobic fibers with endurance and steady power.

Fast-Twitch Muscle Fibers

Anaerobic fibers with explosive power, fatigue quickly.

Catabolism of Protein

Amino acids deaminated and converted for energy pathways.

Catabolism of Fat

Fatty acids broken down to acetyl groups via b-oxidation.

Methanogens

Organisms reducing CO2 to methane in anaerobic respiration.

Lactic Acid Fermentation

Process converting NADH to lactic acid in animals.

Ethanol Fermentation

Process producing ethanol and CO2 in yeast.

Oxidation Without O2

Process using organic or inorganic molecules as electron acceptors.

Evolution of Metabolism

Timeline of metabolic processes from ATP storage to aerobic respiration.