Photosynthesis: An Overview

Photosynthesis

Plants use the energy of sunlight to convert water and carbon dioxide into high-energy carbohydratesPhotosynthesis Equation:

Scientist Investigation

Jan van Helmont (1643)Joseph Preistley (1771)Jan Ingenhousz (1779)

Van Helmont’s Experiment

Measured plant’s water intake and mass increaseConcluded that trees gain most of their mass from water

Joseph Priestley Experiment

Used a jar, candle, flame, and mint leafConcluded that plants give off oxygen

Ingenhousz’s Experiment

Concluded that light is necessary to produce oxygen

What the Experiments Led to:

Other experiments:Discovered that in the presence of light, plants transform carbon dioxide and water into carbohydrates, and they also release oxygen

Process of Photosynthesis

A plant transforms carbon dioxide and waterUsing light energyGives off Oxygen and produces Glucose (a valuable source of energy)

Plants use low-energy raw materials to produce high-energy sugars

Must look at how plants capture energy from then sunPlants gather the sun’s energy with light absorbing molecule~ PIGMENTSThe plants’ principle pigment is chlorophyll a and chlorophyll b

Why are plants typically green?

ROYGBIVChlorophyll absorbs light waves of all colors Reflects the green light