Photosynthesis

What happens? Plants combine water and carbon dioxide to make sugar (glucose) and oxygen Chlorophyll is needed Sunlight provides the energy 6 CO2 + 6 H2O C6H12O6 + 6 O2

Water enters the roots and move to the leaves through xylem CO2 enters through small openings in the leaves called stomata Center of leaves have cells with chloroplasts Contain chlorophyll Capture light energy

Photosynthesis occurs in 2 main stages Light-Independent Reactions Powered by energy from ATP and NADPH CO2 comes in Glucose is produced Light-Dependent Reactions: Sunlight is captured by chlorophyll Water molecules are split – produce O2 Energy molecules are made: a) ATP b) NADPH

These reactions occur in chloroplasts

Once sugar is made it can either be: Used by plant for energy Carried by phloem to roots or stem for storage Oxygen made in the light reactions leaves the leaf through stomata

Why is Photosynthesis Important? Starts most food chains Most autotrophs use photosynthesis to make food Removes CO2 from atmosphere Build up of CO2 contributes to Global Warming