1. 9-1: Cellular Respiration Biology 1

2. Respiration is also used to mean “breathing” Animals use cellular respiration to break down oxygen and sugar into carbon dioxide and water for energy Introduction

3. 1937: Hans Krebs discovered that sugar gets broken down when oxygen is available Sugar gets broken down into citric acid and carbon dioxide gets released by cells (leaves body when you breathe out) Krebs Cycle

4. Quick energy: sprinting runners need FAST energy! They use what cells have stored first, then make more without oxygen Long term energy: long distance runners have stored lots of sugar (called glycogen), when that is gone they break down fats or muscle for more energy Energy and Exercise

5. Photosynthesis Uses sunlight to make energy and sugar (food) PLANT CELLS (only) – chloroplast organelle Needs Carbon Dioxide and Water Makes Sugar and Oxygen sunlight 6 CO 2 + 6 H 2 0  C 6 H 12 O 6 + 6 O 2 Cellular Respiration Uses food that is eaten to make energy ALL CELLS – mitochondria organelle Needs Sugar and Oxygen Makes Carbon Dioxide and Water C 6 H 12 O 6 + 6 O 2  6 CO 2 + 6 H 2 0

6. Photosynthesis and Cellular Respiration are OPPOSITES! Photosynthesis (plants) take carbon dioxide out of air, give back oxygen Cellular Respiration (animals) take oxygen out of air, give back carbon dixoide Comparing Photosynthesis and Cellular Respiration