Metabolism Catabolism Anabolism

First Law of Thermodynamics Eating Where does the energy come from? Where does it go?

First Law of Thermodynamics Walking up a hill Where does the energy come from? Where does it go? Sledding down a hill

Has energy been created or destroyed?

First law of thermodynamics Energy cannot be created or destroyed

Second law of thermodynamics Energy transfer is not completely efficient, therefore… Every energy transfer or transformation increases the entropy of the universe Entropy – Disorder or randomness

Second law of thermodynamics Need energy to decrease entropy Ex. Cleaning your room Do not need energy to increase entropy (Spontaneously) Ex. Your room gets messy without work

Energy and reactions Energy – the capacity to do work Work = force x distance moved

Energy and reactions What is the unit on the y axis? Energy (Gibbs free energy) Which graph represents more capacity to do work?

Energy and Reactions

Exergonic and Endergonic reactions

This is called energy coupling Why is this important? The cells use exergonic processes to drive endergonic processes. This is called energy coupling

Think of a real life example of a primary action that stores potential energy for a secondary action. (ex: pumping water into a holding tank then allowing it to flow through a turbine when electricity is needed)

ATP!!!! ATP couples reactions within the cell What do you think regenerates ATP? Catabolism!!!! (cellular respiration)