Presentation on theme: "Photosynthesis. Autotrophs Plants and some other types of organisms that contain chlorophyll are able to use light energy from the sun to produce food."— Presentation transcript:
Autotrophs Plants and some other types of organisms that contain chlorophyll are able to use light energy from the sun to produce food.
Heterotrophs Heterotrophs are organisms that can NOT make their own foodHeterotrophs are organisms that can NOT make their own food Heterotrophs can NOT directly use the sun’s energyHeterotrophs can NOT directly use the sun’s energy
What is photosynthesis? Process by which a cell captures sunlight and uses it to make food. Photo = light Synthesis = to make
Photosynthesis –Occurs in plants, algae, many types of protists, and some bacteria (a) Plants (b) Multicellular algae (c) Unicellular protist 10 m 40 m (d) Cyanobacteria 1.5 m (e) Purple sulfur bacteria
The Photosynthesis Equation
Chloroplasts: The Sites of Photosynthesis in Plants Vein Leaf cross section Figure 10.3 Mesophyll CO 2 O2O2 Stomata Any part of the plant that is green contains chloroplasts.
10 Stomata (stoma) Pores in a plant’s cuticle through which water vapor and gases (CO 2 & O 2 ) are exchanged between the plant and the atmosphere. Guard Cell Carbon Dioxide (CO 2 ) Oxygen (O 2 ) Found on the underside of leaves Stoma
Light Energy Light from the sun appears white, but is actually composed of a variety of colors. White light is made up of 7 colors ranging from red to violet This is known as the visible spectrum. ROYGBIV
Pretty Colors All colors are present in white light. The color you see is reflected. All the other colors are absorbed. White objects reflect all the colors Black objects absorb all the light.
Light and Pigments In addition to water, carbon dioxide, and light energy, photosynthesis requires Pigments Chlorophyll is the primary light-absorbing pigment in autotrophs Chlorophyll is found inside chloroplasts
Light Absorption in chloroplasts
Chlorophyll Pigments Chlorophyll appears green because it reflects green and absorbs all other colors. Types of Pigments –Chlorophyll a –Chlorophyll b –Carotenoids –Xanophyll
Types of Chlorophyll Chlorophyll a – absorbs blue-violet and red light and reflects green Chlorophyll b - absorbs blue and orange light and reflects yellow-green Carotenoids – absorb blue-green light and reflect yellow-orange Xanophyll- reflects red and absorbs all other colors Chlorophyll b and Carotenoids are examples of accessory pigments. –They allow plants to absorb more light
Factors Affecting the Rate of Photosynthesis Amount of available waterAmount of available water TemperatureTemperature Amount of available light energyAmount of available light energy