18.1 METABOLISM AND ATP ENERGY

ATP

The energy-storage molecule that links energy-producing reactions with energy-requiring reactions in the cells.

Metabolism

All chemical reactions that provide energy and substances needed for growth.

Catabolic Reactions

Reactions that break down large, complex molecules to provide energy and smaller molecules.

Anabolic Reactions

Reactions that use ATP energy to build larger molecules.

Stage 1 of Metabolism

Digestion and hydrolysis that break down large molecules to smaller ones that enter the bloodstream.

Stage 2 of Metabolism

Degradation that breaks down molecules into two- and three-carbon compounds.

Stage 3 of Metabolism

Oxidation of small molecules in the citric acid cycle and electron transport provides ATP energy.

Hydrolysis of ATP

The process that releases energy by converting ATP to ADP and inorganic phosphate.

Energy from ATP Hydrolysis

Used during muscle contraction, moving substances across cellular membranes, sending nerve signals, or synthesizing an enzyme.

ATP to ADP Reaction

ATP hydrolysis to ADP releases 7.3 kcal per mole of ATP.

Adenosine Monophosphate (AMP)

Formed when ADP hydrolyzes further, along with an inorganic phosphate (Pi).

Energy Storage in the Body

Energy is primarily stored as adenosine triphosphate (ATP).

Cyclic Process of Metabolism

Involves catabolic reactions breaking down food into smaller molecules that can be oxidized for energy.

Importance of Hydrolysis

Essential for releasing energy for cellular functions from ATP.

Chemical Reactions for Growth

Metabolism encompasses all chemical reactions necessary for providing energy and substances for growth.

Complex Molecules

Large molecules that are broken down during catabolic reactions for energy.

Smaller Molecules in Metabolism

Products of catabolic reactions that can be oxidized to produce energy.

Energy-Requireing Reactions

Anabolic reactions that build larger molecules using ATP.

Digestion Role in Metabolism

Stage 1 involves breaking down food for absorption into the bloodstream.

Citric Acid Cycle

Stage 3 of metabolism where oxidation of small molecules occurs to produce ATP.

Electron Transport in Metabolism

Stage 3 component where energy is produced from oxidation of small molecules.

7.3 kcal/mole

The amount of energy released upon the hydrolysis of one mole of ATP.

ATP Cycle

The continuous process of ATP being hydrolyzed to release energy and generate ADP and AMP.

Biochemical Energetics

The study of energy flow through biological systems, particularly involving ATP.

Homeostasis and ATP

ATP plays a critical role in maintaining cellular functions and homeostasis.

Recycling of ATP

ATP can be regenerated from ADP through cellular respiration and energy-producing reactions.

Role of Inorganic Phosphate (Pi)

A component released during ATP hydrolysis which is essential for other biochemical processes.

Energy Production Pathways

The various stages of metabolism that lead to the production of ATP for cellular functions.

Nutrient Utilization in Metabolism

Refers to how the body breaks down food sources into usable energy.

Hydrolysis Reaction Products

ADP and inorganic phosphate (Pi) are the main products of ATP hydrolysis.

Biological Significance of ATP

ATP is crucial for energy transfer in cellular processes across all living organisms.

Feedback in Metabolic Pathways

The regulation of metabolism through signaling mechanisms that depend on ATP levels.