Ch. 8 An Introduction To Metabolism Flashcards
What is Metabolism?
The totality of an organism’s chemical reactions
What is energy?
The capacity to cause change
Free energy
Energy available to do work in a living system when temperature and pressure are uniform
Free energy change = 🔼 G (this is how it’s abbreviated)
What is kinetic energy
Energy associated w/ motion
Heat (aka thermal energy)
Is kinetic energy associated w/ random movement of atoms or molecules
Potential energy
Energy that matter possesses b/c of it’s location or structure
What is this an example of?
The contraction of leg muscles pushes bicycle pedals
Kinetic energy
What is this an example of?
Water behind a dam, for instance possesses energy b/c of the altitude above sea level
Potential energy
What type of energy is contained in chemical bonds in a molecule?
Chemical energy
What are the characteristics of an endergonic reaction?
Absorbs free energy from it’s surroundings; essentially stores free energy in molecules so
🔼G is positive
What are the characteristics is exergonic reaction
Proceeds w/ a net release of free energy; b/c the chemical mixture loses free energy 🔼 G is negative
What are the characteristics of an anabolic reaction?
It links simple molecules to form complex ones (endergonic)
What are the characteristics of catabolic reaction?
Breaks down complex molecules into simpler ones ( exergonic)
What is energy coupling
The use of an exergonic process to drive an endergonic one; most energy coupling in cells is mediated by ATP
What is the general structure of ATP?
3 phosphate groups, sugar ribose, and the nitrogenous base adenine
What type of charge do the phosphate groups possess?
Negative charge
ATP has 3 phosphate groups. Which phosphate group is broken off to release energy?
Terminal phosphate bond / Triphosphate group
Which phosphate groups is added to re-build ATP?
Inorganic phosphate + ADP + energy = ATP