BIOENERGETICS

Bioenergetics energyliving systems organismsThe study of energy in living systems (environments) and the organisms (plants and animals) that utilizing them.

Energy CapacityperformCapacity to perform work. Two examples:Two examples: 1.Kinetic energy 2.Potential energy

Kinetic Energy Energyprocess of doing workEnergy in the process of doing work. Energy of motionEnergy of motion. Examples:Examples: 1.Heat 2.Light energy SUN

Potential Energy Energymatter occupies location, arrangement, or positionEnergy that matter occupies because of it’s location, arrangement, or position. Energy of positionEnergy of position. Examples:Examples: 1.Water behind a dam 2.Chemical energy (gas) GAS

Thermodynamics studyenergy transformations collection of matterThe study of energy transformations that occur in a collection of matter. Two Laws:Two Laws: 1.First Law of Thermodynamics 2.Second Law of Thermodynamics

First Law of Thermodynamics Energycreated or destroyed convertedEnergy cannot be created or destroyed, but only converted to other forms. universe is constantThis means that the amount of energy in the universe is constant.

Second Law of Thermodynamics energy transformations inefficient increase entropylossenergyheat.All energy transformations are inefficient because every reaction results in an increase in entropy and the loss of usable energy as heat. EntropyEntropy: the amount of disorder in a system.

Endergonic Reactions Chemical reaction energyChemical reaction that requires a net input of energy. Example:Example: 1. Photosynthesis 6CO 2 +6H 2 O  C 6 H 12 O 6 + 6O 2 SUN photons Light Energy (glucose)

Exergonic Reactions Chemical reactionsreleases energy.Chemical reactions that releases energy. Example:Example: 1.Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP (glucose)Energy

Cellular Metabolism sum total chemical activities cellsThe sum total of the chemical activities of all cells. EndergonicExergonicEndergonic and Exergonic reactions 2 Examples:2 Examples: 1.Anabolic Pathways 2.Catabolic Pathways

Anabolic Pathway Metabolic reactions, consume energy (endergonic),buildMetabolic reactions, which consume energy (endergonic), to build complicated molecules from simpler compounds. Example:Example: 1.Photosynthesis 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 SUN lightenergy (glucose)

Catabolic Pathway Metabolic reactions release energy (exergonic)breaking downMetabolic reactions which release energy (exergonic) by breaking down complex molecules in simpler compounds. Example:Example: 1.Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP (glucose) energy

Question: ATP?What is ATP?

Answer: adenosine triphosphate (ATP)adenosine triphosphate (ATP) Components:Components: 1.adenine:nitrogenous base 2.ribose:five carbon sugar 3.phosphate group: chain of three ribose adenine PPP phosphate group

Question: How does ATP work?How does ATP work?

Answer: direct chemical transfer phosphate group.Works by the direct chemical transfer of a phosphate group. “phosphorylation”This is called “phosphorylation”. exergonic hydrolysis ATP endergonic processes transferring phosphate groupThe exergonic hydrolysis of ATP is coupled with the endergonic processes by transferring a phosphate group to another molecule.

Hydrolysis of ATP ATP + H 2 O  ADP + P (exergonic) Hydrolysis (add water) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP)

Dehydration of ATP ADP + P  ATP + H 2 O (endergonic) Dehydration synthesis (remove water) (remove water) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP)