Presentation on theme: "1 Review Why are pigments such as chlorophyll needed for photosynthesis Predict How well would a plant grow under a pure yellow light- Explain 2 Review."— Presentation transcript:
1 1 Review Why are pigments such as chlorophyll needed for photosynthesis Predict How well would a plant grow under a pure yellow light- Explain 2 Review What is the function of NADPH Infer How would photosynthesis be affected if there were a shortage of NADP+ in the cells of plants. 3 Visual Thinking Draw two leaves- one green and one orange. Show which colors of visible light are absorbed and which are reflected by each leaf.
2 8.2 Photosynthesis: An Overview Ch 8 Photosynthesis8.2 Photosynthesis: An Overview
3 Light Energy from the sun travels to Earth in the form of light Sunlight is a mixture of different wavelengthsSome are visible to us some are not.
4 PigmentsLight absorbing molecules that gather the sun’s energyChlorophyllPlants primary pigment.
5 ChlorophyllTwo typesChlorophyll a and chlorophyll bAbsorb blue-violet and red regions of the spectrumThey appear green.
6 Carotene Red orange pigment Secondary pigment, chlorophyll hides it most of the yearChlorophyll breaks down earlier in the fall which gives leaves the fall colors.
7 Chloroplasts Organelle where photosynthesis occurs Thylakoids Grana Saclike photosynthetic membranes in chloroplastsGranaInterconnectedstacks of thylakoidsStromaFluid portion outside of the thylakoids.
8 Energy CollectionChlorophyll absorbs light and is transferred to electrons.
9 High-Energy Electrons Are highly reactive and require a special “carrier”Carriers include:NADP+Accepts and holds two high-energy electrons, along with a hydrogen ion (H+)Turns into NADPH which carries the electrons.
10 Photosynthesis Steps“Plant” absorbs light energy and takes in CO2 and H2O“Plant” releases O2 and makes sugar (glucose C6H12O6).
11 Photosynthesis involves two sets of reactions Light-dependent reactionsLight-independent reactions.
12 Light-Dependent Reactions Use energy from sunlight to produce ATP and NADPHOccurs in ThylakoidRequires water and releases oxygen.
13 Light-Independent Reactions ATP and NADPH molecules produce high-energy sugars from carbon dioxideLight is not neededOccurs OUTSIDE of thylakoid but IN stroma.