Chapter 9 Cellular Respiration Chemical Pathway

Calorie (C) ●The amount of energy needed to raise the temp of 1 gram of water 1 degree C. ●They are released as forms of energy from burning sugars etc.

Glycolysis Release very little energy In the presence of O2 2 pathway that release a lot of energy In the absence of O2 followed by different pathway

Cellular Respiration A process that releases energy by breaking down carbohydrates and O2 to, produce CO2, water, and energy

Glycolysis A process by which 1 molecule of glucose is broken in 1/2 , producing 2 molecules of Pyruvic acid (A 3 Carbon Compound) In this process ATP and NADH are produced alongside Pyruvic Acid

Chemical Pathways C C C C C C Glucose ATP ATP ATP CO2 H2O Glycolysis Krebs Cycle Electron Transport O2 Fermentation Alcohol or (without oxygen) Lactic Acid C C C C C C ATP ATP ATP

Fermentation ●Release energy from food molecules in the absence of O2 ●Anaerobic – “Without Air” ●Convert , NADH NAD, so glycolysis can continue to produce ATP 2 Types ▪Lactic Acid ▪ Alcoholic

Alcoholic Fermentation Used by yeast Forms Ethyl Alcohol and CO2 as waste Causes bread dough to rises

Lactic Acid Fermentation

Lactic Acid Produces Lactic Acid and NAD+ so glycolysis can continue Produced in muscles when O2 supply runs out Reason for muscle soreness

Krebs Cycle Pyruvic Acid is broken down into CO2 in a series of energy – extracting reactions The source of CO2 in your breath Produces ATP for cellular activities

Electron Transport Krebs Cycle produces e-; that are passed to NADH which are passed from these carriers to an e- transport chain Uses high energy e- from Krebs Cycle to convert ADP to ATP

Glycolysis With No O2 2 ATP Produce 2 ATP & Glucose With No O2 2 ATP With O2 present Krebs Cycle (34 ATP) + 2ATP This is about 38% of the total energy of glucose, the rest (62%) is released as heat This is why we feel warmer after exercise

Glycolysis

Energy & Exercise Quick Energy the body uses Stored Energy 1st but then depends on Lactic Acid fermentation after the 1st few seconds (can last for 90 seconds)

Long Term Energy Cellular Respiration releases energy slowly then Lactic Acid form Body uses stored carbohydrates (glycogen) last 15-20 min After this, the body begins to break down others sources of energy, such as fats Called “Aerobic” exercise

Respiration: An Overview