Photosynthesis & Respiration

Photosynthesis Process by which AUTOTROPHS use energy from the sun to produce GLUCOSE from carbon dioxide and WATER

Carbon dioxide + water  Glucose + Oxygen

Light Reactions Occurs in chloroplast LIGHT ENERGY is turned into CHEMICAL ENERGY. WATER is used – provides electrons. Water is ABSORBED from soil through the roots. OXYGEN is released into the atmosphere.

CALVIN CYCLE Occurs in CHLOROPLAST Uses ENERGY from the light reactions and CARBON DIOXIDE from the atmosphere to make GLUCOSE, which is FOOD for the plant. The CARBON DIOXIDE enters the plant through the STOMA on the surface of the leaf.

Factors that Affect Photosynthesis WATER availability TEMPERATURE Light INTENSITY

Organisms that Perform Only photosynthetic organisms, including PLANT, some protists, and some bacteria.

Carbon Dioxide and Water During Photosynthesis which molecules does a plant cell obtain (get) from the air or soil? (Hint: look at the equation ) Carbon Dioxide and Water

Which reactant is used in the light reactions? Which reactant is used in the Calvin Cycle? Which product is made in the light reactions? Which product is made in the Calvin Cycle?

What does carbon dioxide provide? What does water provide? What happens to glucose after it is made? What happens to oxygen after it is made?

Why is this important to us? We cannot make our own food (glucose, energy), we must get our food from plants. Plants are one of first links in the food chain. The oxygen released during photosynthesis is necessary for all living things. As a matter of fact, as much as 90% of the oxygen in our atmosphere is the result of photosynthesis.

What is the equation for the chemical reaction of photosynthesis? Six molecules of carbon dioxide react with six molecules of water to form 1 molecule of glucose and six molecules of oxygen.

How do CO2 and H20 enter/leave the leaf? Stomata: small openings in the leaf’s surface Provides opening for CO2 and O2 to enter and leave plant

Summary The goal of photosynthesis is to make glucose from light energy! Sun Chlorophyll CO2 + H20 C6H12O6 + O2 (glucose)