Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint Lectures for Biology: Concepts and Connections, Fifth Edition – Campbell, Reece, Taylor, and Simon Lectures by Chris Romero Chapter 7 Photosynthesis: Using Light to Make Food

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.0 Photosynthesis - makes sugar and oxygen gas from - carried out by - ultimate source of all - major source of

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Photosynthesis can meet growing – plantations of renewable environmentally safer than

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings AN OVERVIEW OF PHOTOSYNTHESIS 7.1 Autotrophs - the producers of - produce their - produce the food supply for

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.2 Photosynthesis - occurs in - occurs primarily in - ____ enters and ____ exits - through ____________________

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Chloroplast structure – Stroma Location of – Thylakoids Contain

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.3 Plants produce - by splitting - the O 2 given off by photosynthesis is made from

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.4 Photosynthesis occurs in two stages linked by ATP and NADPH Light reactions – Occur in – Convert light energy to chemical energy as – Produce O 2 as a Calvin cycle – Occurs in – Assembles sugar molecules from CO 2 using ATP and NADPH energy from

THE LIGHT REACTIONS: CONVERTING SOLAR ENERGY TO CHEMICAL ENERGY 7.5 Sunlight is - electromagnetic - radiation travels as - the distance between waves = Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

Thylakoids of the - contain several - absorb some - reflect Chlorophyll a - reflects Chlorophyll b - reflects Carotenoids -

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.6 Photosystems capture When a pigment molecule absorbs energy: – an electron is raised in energy from – it then rapidly drops back to – the electron releases excess – some pigments also

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.7 In the light reactions, electron transport chains generate Photosystem II – A pigment molecule – The excited electrons are passed to an - providing energy to - water is ____________, releasing ___

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Photosystem I – energy is – excites an electron of _____________ which - passes through an

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings THE CALVIN CYCLE: CONVERTING CO 2 TO SUGARS 7.8 The Calvin Cycle makes – Inputs carbon from energy from – Output organic

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PHOTOSYNTHESIS REVIEWED AND EXTENDED 7.9 Photosynthesis uses light energy to make The light reactions – Capture – Generate – Release The Calvin cycle – Manufactures

Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings 7.10 Plants have special adaptations to - rate of photosynthesis decreases in - stomata closed in - to prevent - very dry climates - open stomata and admit

PHOTOSYNTHESIS, SOLAR RADIATION, AND EARTH'S ATMOSPHERE: CONNECTION 7.11 The greenhouse effect – Like a greenhouse, the atmosphere traps ____ and other gases that absorb – Excess greenhouse gases in the atmosphere contribute Photosynthesis - removes CO 2 from - moderates Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

TALKING ABOUT SCIENCE 7.12 Earth's protective ozone layer pollutants are affecting Earth's ozone layer – solar radiation converts ______ high in the atmosphere to – the ozone layer shields organisms on Earth's surface from – ___________ have caused dangerous thinning of the ozone layer