Brenda - Energetics

Question 1

Define bioenergetics

Answer 1

The quantitative study of the energy transductions that occur in living cells and of the nature and function of the chemical processes underlying these transductions

Question 2

Define metabolism

Answer 2

Metabolism is the sum of all the chemical transformations taking place in a cell or organism, occurs through a series of enzyme-catalyzed reactions that constitute metabolic pathways

Question 3

How can metabolic pathways be divided?

Answer 3

Into two phases:
- Biosynthesis (anabolism)
- Degradation (catabolism)

Question 4

What is biosynthesis (anabolism)?

Answer 4

Whereby small simple precursors are used as building blocks for larger macromolecules. This requires energy

Question 5

What is degradation (catabolism)?

Answer 5

Whereby macromolecules are broken down into smaller simpler end products. This liberates energy.

Question 6

What is the first law of thermodynamics?

Answer 6

Conservation of energy

Energy cannot be created or destroyed, merely converted from one form to another

Question 7

What is the second law of thermodynamics?

Answer 7

Every time energy is changed, there will be an increase in the entropy (disorder) of the universe

Question 8

What is Gibbs free energy, G?

Answer 8

A measure of the amount of energy which is available to do work, at constant T and P

Question 9

What is enthalpy (H)?

Answer 9

Heat content
- usually the number and type of bonds

Question 10

What is entropy (S)?

Answer 10

Disorder
- usually the number of molecules

Question 11

What is standard free energy change?

Answer 11

It describes the position of the equilibrium of a reaction