 Photosynthesis is the process by which plants use the sun’s energy to convert water and carbon dioxide into sugars.  Read “Energy” p. 327 – 329  Take Notes!

 Energy is the ability to do work.  Kinetic energy is the energy of motion  Potential energy is energy that is stored due to an object’s position or arrangement.  Energy can be converted from one form to another.  Different types of energy – chemical, light, electrical, mechanical, thermal

 Organic molecules have a form of potential energy called chemical energy  Chemical energy has the potential to do work due to the arrangement of the atoms within the molecules.  The rearrangement of atoms during chemical reactions releases the potential energy, and the energy is then available to do work.

 Photosynthesis is the process by which plants use the sun’s energy to convert water and carbon dioxide into sugars.  Light is the only source of energy for plants!  Plants convert light energy into chemical energy -> Photosynthesis  Recall that light is energy  Different colors of light have different wavelengths and different amounts of energy.  Red light = low energy  Blue light = high energy

Light is a form of energy called Electromagnetic energy.

 A substance’s color is due to chemical compounds called pigments.  When light hits an object the wavelengths can be transmitted, absorbed, or reflected.

 Chloroplasts contain pigments called Chlorophyll a, Chlorophyll b, and Carotenoids.  Each pigment absorbs different wavelengths of light.

 Notice that chloroplasts absorb blue-violet and red-orange light very well.  The chloroplasts convert the absorbed light energy into chemical energy.  Why are leaves green?  Why do leaves change colors in the fall?  Complete Stop & Think #1-4 p. 329

 Read “Making Carbon Compounds” p  Take notes!  Read “Energy Currency of Cells” p. 333  Take Notes.