What are the two laws of thermodynamics, and how do they relate to organisms?

1 Answer
Nov 12, 2015

In general, thermodynamics is the study of the changes in energy that accompany events in the universe.


The first law of thermodynamics – the law of conservation of energy.
It says that energy can neither be created nor destroyed. What we have in the universe is all there is! But, energy can be transformed from one form to another (i.e. chemical, kinetic, potential, light etc.)
Example: Chemical energy is converted to mechanical energy when heat is released during muscle contraction.

The second law of thermodynamics - events in the universe tend to proceed from a state of higher energy to a state of lower energy.
These events are called spontaneous, since they can occur without the input of external energy.
- Every transformation of energy increases entropy (S); which is a measure of randomness or disorder.
- Entropy of a system may decrease, but the overall entropy of the universe increases
- Like what my Professor says, "...there is no free lunch"