8-2: Photosynthesis Biology 1

Plants use sunlight to change water and carbon dioxide (CO 2 ) into sugar sunlight 6 CO H 2 0  C 6 H 12 O O 2 sunlight Carbon + Water  Sugar + Oxygen Dioxide Introduction

1600: Jan van Helmont created an experiment to find out how plants grow Decided that plants grow by using taking water Didn’t know plants use carbon dixoide in the air to make sugar (for food) Investigating Photosynthesis

1700: Joseph Priestly decided to try van Helmont’s experiment again Put plant under a jar with a candle Plant used carbon dioxide (from the candle) and gave off oxygen (to keep candle burning) Investigating Photosynthesis

1780: Jan Ingenhousz showed that Priestly’s experiment only worked if the plant had sunlight Other scientists used the information from van Helmont, Priestly and Ingenhousz’s experiments to show that in sunlight, plants change carbon dioxide and water into sugar and oxygen Investigating Photosynthesis

Bill Nye the Science Guy Respiration (part 1) (part 2) (part 3)