Cellular Respiration Chemical Energy Cellular Respiration is how

Cellular Respiration

Chemical Energy Cellular Respiration is how your cell turns the food you eat into energy for your cells. p Calorie: the amount of energy needed to raise the temperature of water 1°C p

Cellular Respiration p Overview: n The mitochondria in cells breaks down glucose and produces energy in the form of ATP.

Cellular Respiration 6 O 2 + C 6 H 12 O 6 6 CO 2 + 6 H 2 O + ENERGY * The equation for cellular respiration is just photosynthesis backwards!

Energy Production p There are 2 ways for a cell to make energy depending on the presence of oxygen… 1) Fermentation (anaerobic) 2) Cellular Respiration (aerobic)

Energy Production Prefix review: A- : means without Aero- : means air or oxygen Therefore…. p Aerobic means with oxygen Anaerobic means without oxygen

Energy Production BOTH ways a cell makes energy starts with Glycolysis p Glycolysis: The process in which glucose is split n Happens in the cytoplasm n Happens in all living organisms

Energy Production

Cellular Respiration p Three stages of cellular respiration 1. Glycolysis - anaerobic 2. The Krebs Cycle (aka: Citric Acid Cycle) - aerobic 3. The electron transport chain – aerobic * The aerobic stages create the most ATP

3 Stages of Cellular Respiration Step 1: Glycolysis p Starts with glucose p Produces ATP, electron carrier, & pyruvate p Occurs in cytoplasm

3 Stages of Cellular Respiration Step 2: Krebs cycle ( AKA citric acid cycle) p Starts with pyruvate (converted to acetyl-Co. A) p Produces CO 2 , ATP, & electron carriers p Occurs in matrix of the mitochondria

The Krebs Cycle (Citric Acid Cycle)

Cellular Respiration p STEP 3: Electron Transport Chain n Uses high energy electrons (from Krebs) and Oxygen n Produces ATP and water n Occurs in the inner mitochondrial membrane

The Electron Transport Chain

Cellular Respiration p The Whole Package… Produces 38 ATP!

Fermentation p Happens when there is NO oxygen present p Anaerobic means without oxygen p Produces less energy than aerobic respiration

Alcoholic Fermentation Occurs in cytoplasm of bacteria & yeast p Starts with pyruvate (from glycolysis) p Produces ethyl alcohol & carbon dioxide p Uses: makes alcohol & bread p

Lactic Acid Fermentation Occurs in cytoplasm of muscle cells & bacteria p Starts with pyruvate (from glycolysis) p Produces lactic acid p Causes. . . burning sensation after vigorous exercise p Uses: makes sauerkraut & yogurt p

Energy Use p Quick Energy: ex. Sprints. n Energy obtained through lactic acid fermentation n Why you feel a burning sensation p Long-Term Energy: energy made by cellular respiration

The Big Picture Aerobic Cell Respiration -Uses Oxygen -Produces 38 ATP Anaerobic Fermentation -No Oxygen -Produces only 2 ATP