Biochemistry Test (Bioenergetics)

What is thermodynamics?

Branch of physics that deal with heat, work, energy and laws governing energy transfer and transformation in systems

What is Bioenergetics?

It studies energy transduction within living cells and the nature and function of the chemical processes underlying these transductions.

What is energy?

The capacity to do work or bring about change

What is a system?

A part of the universe separated from its surrounding by a real or imaginary boundary

Measurement of energy?

Joules or Calorie

The universe consists of?

A system and its entire surroundings

Types of system?

Open system: Exchange of energy and matter with its surroundings. E.g living organism.

Closed system: Exchanges energy but not matter with its surroundings. E.g a sealed container of gas.

Isolated system: Exchanges neither energy nor matter with its surroundings. E.g The universe

State the First Law of thermodynamics

The total amount energy of in an isolated system remains constant. Energy can neither be created nor destroyed.

Laws of Conservation

State the 2nd Law of Thermodynamics

The entropy of the entire universe as an isolated system will always increase over time.

T/F: Cells are efficient transducers of energy and can interconvert between different forms of energy

True

Living organisms get energy by?

Flow of electrons

What is Entropy?

The measure of disorderliness in a system

In reactions with increased disorderliness, Entropy is?

Positive

How does living organisms preserve internal orderliness?

By taking energy in form of nutrient and sunlight from its surroundings and returning equal amount of energy as heat and entropy

What is Gibbs Free Energy?

The amount of energy available to do work

Formula for Free Energy?

G = H - TS

What is Enthalpy?

The total heat content of a reacting system.

Formula for Enthalpy?

H = U + PV

For a spontaneous reaction, change in free energy must be?

Negative

When change in free energy is zero, it means?

Equilibrium

What is an equilibrium system ?

A system or point at which both the forward process and reverse process are taking place at the same rate.