Energy

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Energy and all its relations

Energy is the capacity to do work; it can be converted from one form to another.

Energy can exist in one of two states which are interconvertible;

Kinetic Energy: Energy of an object in motion

A Falling Rock, electricity and Light

Potential Energy: Stored energy

A rock at the top of a hill or chemical energy

Laws of Thermodynamics (As applied to Biology)

Thermodynamics is the study of energy and its transformation

1st Law

Energy cannot be created or destroyed, but can be transformed from one form to another.

This is also known as principle of conservation of energy

2nd Law

The total disorder (entropy) of a system and its surroundings always increases

Although the total energy in the universe does not change

When discussing thermodynamics, scientist refer to a system (object studied) and everything outside of it as its surroundings.

Three types of systems:

Isolated System : does not exchange mater or energy with its surroundings

Closed System: exchanges energy with its surroundings

Open system: exchanges both energy and matter with its surroundings