1.-performance of mechanical energy

2.-active transport of molecules and ions

3.-synthesis of macro molecules and other biomolecules from simple precursors

Basic Principles that underlie E flow in all living systems

1.-Fuels are degraded & large molecules constructed by metabolic pathways

2.-ATP links E releasing and E requiring pathways

3.-oxidation of C fuels power ATP formation

4.-limited # of types of rxn's and particular intermediates common to many pathways

5.-Metabolic pathways highly regulated to allow efficient use of fuels and coordinate biosynthetic processes.

1.-ones that convert E from fuels into biologically useful forms such as ATP or ion gradients

2.-ones that require inputs of E to proceed

Catabolic Reactions

(Catabolism)

rxns that transform fuel into cellular E

Fuel -> CO₂ + H₂O + Useful E

Anabolic Reactions

(Anabolism)

rxns that require E

Useful E+simple precursors -> complex molecules

pathways that can be either anabolic or catabolic, depending on the E conditions in the cell

1. individual rxns must be specific
2. entire set of rxns that constitute pathway must be thermodynamically favored

ΔG⁰¹ + RTln [C][D]

[A][B]

• Adenine
• Ribose
• Triphosphate unit

1. adenosine diphosphate + orthophosphate
2. adenosine monophosphate + pyrophosphate

1. Electrostatic repulsion
2. Resonance stabilization
3. Stabilization d/t hydration