Key Concepts in Biochemistry: Energy Metabolism

Vocabulary flashcards covering key terms and concepts related to energy metabolism in biochemistry.

Phototroph

Organisms that obtain energy by trapping sunlight in a chemical form.

Chemotroph

Organisms (including humans) that obtain energy through the oxidation of carbon fuels.

Metabolism

A linked series of chemical reactions that converts biomolecules into other required biomolecules.

Metabolic pathways

Series of linked reactions where fuels are degraded and large molecules are constructed step by step.

ATP (adenosine triphosphate)

The energy currency common to all life forms, linking energy-releasing pathways with energy-requiring pathways.

Catabolism

Reactions that extract energy from fuels.

Anabolism

Reactions that use energy to synthesize complex molecules from simpler precursors.

Amphibolic pathways

Pathways that can function as either anabolic or catabolic depending on the energy conditions in the cell.

Hydrolysis of ATP

An exergonic reaction that releases free energy to drive cellular processes.

Free energy change (ΔG)

The change in free energy that determines whether a reaction occurs spontaneously.

Resonance stabilization

Stability due to the presence of multiple resonance forms in products.

Phosphoryl-transfer potential

The tendency of a phosphorylated compound to transfer its phosphoryl group.

Nicotinamide adenine dinucleotide (NAD+)

A major electron carrier in the oxidation of fuel molecules.

Flavin adenine dinucleotide (FAD)

Another electron carrier in the oxidation of fuel molecules.

Reversible covalent modification

Modification of enzyme activity through the addition or removal of functional groups.

Allosteric control

Regulation of enzyme activity through the binding of effectors at sites other than the active site.

Energy charge

The fraction of all adenine nucleotides in the form of ATP, plus half the fraction in the form of ADP.

Gluconeogenesis

The metabolic pathway that generates glucose from non-carbohydrate substrates.

Creatine phosphate

A high-phosphoryl-transfer-potential molecule that serves as a reservoir of phosphoryl groups in muscle.

Oxidation-reduction (redox) reactions

Reactions that involve the transfer of electrons, where one molecule is oxidized and another is reduced.

Feedback inhibition

A regulatory mechanism in which the final product of a metabolic pathway inhibits an earlier step in the pathway.

Thermodynamic favorability

The capacity of a reaction to occur spontaneously based on free energy considerations.

Biochemical ecosystem

The interconnected nature of metabolic pathways within a cell.

Compartmentalization

The segregation of different metabolic pathways in eukaryotic cells, enhancing regulation.

Phosphorylation potential

The energy available from the hydrolysis of phosphorylated compounds.

Activated carrier

Molecules that carry reactive groups in metabolic processes, such as NADH and coenzyme A.

Vitamins

Organic compounds required in small amounts in the diet, often serving as precursors to coenzymes.

Hydrotrope

A molecule that aids in dissolving proteins and preventing aggregation in biological systems.

Substrate accessibility

Regulation of metabolic pathways through the control of substrate availability.

Homeostasis

The stable biochemical environment that must be maintained in living organisms.