Introduction to Energy Systems

A note about labs  Bench press bar = 10 kg  Need to go through and complete bothe the results and questions for the lab, and  Fitness prescription for your “athlete”  Next week  carb loaders

WebCT  Discussion boards  Week 2 Links Lectures

Today  Focus on What is energy How is food  energy Basics catabolism and anabolism Anaerobic synthesis ATP Aerobic synthesis ATP

Types of energy Chemical Mechanical Heat Light Electric Nuclear

Laws of Thermodynamics  energy transfer always proceeds in the direction of increased entropy and the release of free energy  1- Energy cannot be created or destroyed Chemical energy  mechanical energy

Definitions  Enzymes Highly specific protein catalysts Accelerate the forward and reverse reactions Are neither consumed nor changed in the reaction  Coenzymes Complex nonprotein organic substances facilitate enzyme action by binding the substrate with its specific enzyme

Catabolism : Metabolic pathways that break down molecules into smaller units and release energy Catabolism and Anabolism +

Overview of Catabolism GlucoseFFA’sAmino acids glycolysis mitochondria  - oxidation TCA Cycle deamination NH 2 NADH + H + FADH + H + CO 2 Acetyl CoA Electron Transport Chain Figure 3.4, simplified

Anabolism Covalent bonding of electrons, protons and small molecules to produce larger molecules  building up - Catabolism and anabolism function in a dynamic balance. Anna

Adenosine Triphosphate Powers all of cell’s energy-requiring processes Potential energy extracted from food Energy is stored in bonds of ATP g is stored

Adenosine Diphosphate  ADP is ATP minus one phosphate group  14 calories of energy is released each time ATP  ADP

Remember the Spare Phosphate??  The Spare P that was released from ATP  ADP hooks up with Creatine to form …  Creatine Phosphate (CrP)  Cells store ~ 4 – 6 times more PCr than ATP

ATP-PC system  Anaerobic resynthesis of ATP- 5-8 seconds of energy  Hydrolyzed by the enzyme, creatine kinase  ADP is phosphorylated to ATP  Creatine may be phosphorylated back to PCr

Citric Acid Cycle  Also known as the TCA cycle, or Krebs cycle  Continues oxidation of Carbohydrates following glycolysis Fatty acids following beta oxidation Some amino acids following deamination

Summary  Energy is never created nor destroyed.  Complex chemical process synthesize glucose/ glycogen from our foods  Stored as glycogen if not needed  Anaerobic  ATP-PC system  Aerobic  Citric acid/ Kreb’s cycle