Law of thermodynamics

Question 1

What are the laws of thermodynamics?

Answer 1

1st law: Energy is not created nor destroyed in a closed system, but it can be transformed
2nd law: when energy is converted from one form to another, some of that energy becomes unavailable to work

Question 2

How does the 2nd law of thermodynamics apply to biological systems?

Answer 2

Total energy = enthalpy (H)
Free energy (G) = is usable energy that is able to do work
Unusable energy = entropy (S) x absolute temperature. H = G + TS

Question 3

Difference between endergonic and exergonic reactions.

Answer 3

Endergonic - absorbs free energy, -G, where complexity decreases
Exergonic - releases free energy, +G, where complexity increases

Question 4

Characteristics of ATP

Answer 4

• ATP (adenosine triphosphate), captures and releases free energy
• Hydrolyzed to ADP and Pi
• An endergonic reaction
• It donates phosphorylates to other molecules to gain energy