Transcript Producer
What do all living things need? Energy! All living things need a constant flow of energy Top Consumers Primary Consumer Producer Secondary Consumers Carnivores Top Consumer Secondary Consumer Plant Carnivore Primary Consumers Herbivores Decomposers Fungus & Bacteria Herbivore Producers Plants From where do the producers get their energy? From the SUN!!! By what process do the producers capture solar energy & convert it into a usable form for all living things? When we are done with this chapter, you will be able to… 1. Explain why Photosynthesis is necessary 2. Tell where photosynthesis takes place 3. What is the formula for photosynthesis 4. Explain how photosynthesis occurs a) Reactants & products of the Light reaction b) Reactants & products of the Calvin Cycle Chapter 4: Photosynthesis Let’s get into this Energy produced by the producers (with the energy from the sun) is transferred from one organism to the next. Sun Producers Primary Consumers Secondary Consumers Photosynthesis • Process by which green plants or organism with chlorophyll, convert light energy into the chemical energy in the bonds of carbohydrates • Autotrophic – – Can transfer energy to produce food – can make their own food – Plants, some bacteria & some protists • Heterotrophic – – Must obtain energy from preformed food – must eat food – Fungus, all animals, some bacteria & protists What is needed for autotrophs to photosynthesize? • • • • Carbon dioxide (atmospheric) Water (in the soil or air) Sunlight (or artificial light source) Chlorophyll (present in leaves and sometimes stems) General formula for Photosynthesis Where does Photosynthesis take place in a leaf? • Chloroplasts are small oval structures containing the green pigment chlorophyll on the leaves of plants What does a chloroplast look like? Chloroplasts are oval structures consisting of stacked grana (photosynthetic membranes) • and a liquid called stroma. – Chlorophyll is found in the stacked grana Photosynthesis occurs in 2 major steps Light Reaction occurs in the... Calvin Cycle occurs in the... Step 1 – The Light Reaction • Occurs only in the presence of light. – Occurs in the grana (stacks) of the chloroplasts – Light is used to split water molecules into hydrogen and oxygen and to move electrons through the membranes of the grana to produce ATP Light Dependent Reaction Membrane of the Grana Light Independent Reaction Occurs in Stroma Glucose Step 2. Calvin Cycle (Light independent reaction) • can occur in light or darkness. Follows light reaction • Occurs in the stroma of the chloroplasts • CO2 will get “fixed up” with the ATP energy from the light reaction (and hydrogens also from the Light Reaction) to produce Glucose Membrane of the Grana Occurs in Stroma Glucose The Steps in Photosynthesis THE LIGHT REACTION • 1) The light energy strikes the leaf, passes into the leaf and hits a chloroplast inside an individual cell. • 2) The light energy, upon entering the chloroplasts, is captured by the chlorophyll inside a grana. • 3) Inside the grana some of the energy is used to split water into hydrogen and oxygen. Produces ATP molecules • 4) The oxygen is released into the air. The Calvin Cycle (Light Independent Reaction) 5) The hydrogen is taken to the stroma along with the ATP energy from the Light Reaction. 6) Carbon dioxide enters the leaf and passes into the chloroplast. 7) In the stroma, the remaining light energy is used to combine hydrogen and carbon dioxide to make carbohydrates. This occurs during the Calvin Cycle 8) The energy-rich carbohydrates (Glucose) are carried to the plant's cells. H Look at the diagram of photosynthesis from the previous slide. What are the names of the two reactions that are occurring in the chloroplasts Describe what reactants are going in and what products are going out. H Summary Great Summary of Photosynthesis & Respiraton • Animation • Another good one REACTION TYPE What goes into it? What comes out of it? Does it need light? Does it need the dark? What gets split? (What is produced?) Light Reaction Calvin Cycle H2O Oxygen Yes Water No Sunlight CO2 and What goes into the next stage? ATP Hydrogen Glucose No No Hydrogens (from the light reaction) Nicholl Nothing The Glucose will be used for energy for the cell PHOTOSYNTHESIS REVIEW 1. What is the definition of Photosynthesis? 2. What are the reactants for Photosynthesis? 3. What are the products? 4. What happens during the light reaction of Photosynthesis? 5. What is made during the Calvin Cycle? 6. In what structure is chlorophyll found within a chloroplast? PHOTOSYNTHESIS REVIEW 7. What occurs in the stroma of a chloroplast? 8. Does the light reaction have to occur in the light? 9. Does the light independent reaction have to occur in the dark? 10. Why is glucose so valuable to all living things? 11. Why are plants known as autotrophs (or “producers”)?