What is photosynthesis? The process that plants and algae use to create food from sun energy

Autotrophs and Heterotrophs Autotrophs: organisms, like plants, that use light energy from the sun to produce their own food. Plants can “manufacture” their own energy directly, they are self-sufficient so they are considered autotrophs. Most autotrophs use photosynthesis. Heterotrophs: are organisms that obtain energy from foods they consume All other life forms, such as humans, animals, insects and even bacteria, depend on other living things to live so they are all heterotrophs.

ATP and Glucose Glucose is the what is produced by photosynthesis. ATP and glucose are similar because they are both chemical sources of energy used by cells. Glucose is used to store large amounts of energy that can later be made into ATP to provide energy to the plant.

The Photosynthesis equation Photosynthesis uses the energy of sunlight to convert carbon dioxide and water into high-energy sugar and oxygen 6C02 + 6H2O  C6H12O6 +602 This means: “Six molecules of carbon dioxide plus six molecules of water combine in the presence of a green plant and light energy to form one molecule of sugar and six molecules of oxygen.”

Basic Terminology Pigments: Molecules that collect light energy Chlorophyll: The main light absorbing pigment found in green plants Stroma: found in the gel-filled space inside the chloroplast that surrounds the thylakoid stacks. Thylakoid: a membrane-bound compartment inside chloroplast.

Two Cycles of photosynthesis The two cycles that make up photosynthesis are light-dependent reaction and the Calvin cycle. The Light Dependent reaction happens in the Thylakoid. The Calvin cycle is a chemical reaction that occurs in the Stroma.

Light-dependent Reactions Use sunlight and water from outside the cell. The ATP and NADPH are made during the light-dependent reaction for use in the Calvin cycle. They carry energy and high energy electrons that are used during the Calvin cycle. When the water is split during the light-dependent reaction the O in H20 is given off as oxygen

The Calvin Cycle Carbon Dioxide is absorbed through openings called stomata for the Calvin cycle. The Calvin cycle uses energy from the light-dependent reactions and the carbon dioxide to make sugars. NADP and ADP are created for use in the light-dependent cycle.