Section 3.1: Metabolism and Energy

What is a “Metabolism?” -The term “metabolism” is how well our bodies are able to undergo chemical transformations in order for us to sustain life -The set of chemical reactions in living organisms

What is a “Metabolism?” -human life is maintained by the 4 main macromolecules: proteins, lipids, carbs, and nucleic acids (DNA and RNA)

2 Forms of Metabolism: Anabolism And Catabolism

Anabolism -Anabolism is the form of using energy to construct cell components ex. amino acids.

Catabolism: -Catabolism is the form of breaking down large molecules ex. The transformation of nutrients in our bodies.

What Does it Mean to “Burn” Calories? -Calories are forms of energy we consume We convert Chemical Energy into: Kinetic Energy, Heat Energy, Electrical Energy, Sound Energy Ex. Human Body Temp (37°)

Chemical Reactions -In our bodies the energy is changed through a chemical reaction -Bonds between atoms are broken and changed so that the energy can be absorbed or released -We are able to burn/use energy from foods through a Exergonic reaction or an Endergonic reaction

Bond Energy -Energy is required to break bonds -The bond energy is the minimum required energy to break bonds

Activation Energy (Ea) -Energy is required for this reaction called activation energy http://youtu.be/YacsIU97OFc

The 2 types of reactions when this occurs are called exothermic reactions and endothermic reactions. Exergonic Reaction-A chemical reaction where energy is released from the body Endergonic Reaction-A chemical reaction where the energy is absorbed from the body

How to Calculate Energy in a Reaction Ex. The Combustion of Methane:

Combustion Reaction A combustion reaction is when all substances in a compound are combined with oxygen, which then produces carbon dioxide and water.

*Refer to Pg.129 in textbook*