Cells and Energy
Cells and Energy
Cells and Energy
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
MAIN IDEACellular respiration is like a mirror image ofphotosynthesis.ConnectingCONCEPTSPhotosynthesis Review the overallprocess of photosynthesis inSection 4.2 <strong>and</strong> compare photosynthesisto cellular respiration.Photosynthesis <strong>and</strong> cellular respiration are not true opposites, but you canthink about them in that way. For example, chloroplasts absorb energy fromsunlight <strong>and</strong> build sugars. Mitochondria release chemical energy to make ATP.The chemical equation of cellular respiration is also basically the reverse ofphotosynthesis. But the structures of chloroplasts <strong>and</strong> mitochondria aresimilar. A mitochondrion is surrounded by a membrane. It has two parts thatare involved in cellular respiration: the matrix <strong>and</strong> the inner mitochondrialmembrane. In mitochondria, cellular respiration takes place in two mainstages, as shown in FIGURE 4.11.FIGURE 4.11 Cellular Respiration OverviewWhen oxygen is available, ATP is produced by cellular respiration in mitochondria.STAGE 1: Krebs Cycle1Three-carbon moleculesfrom glycolysis entercellular respiration inmitochondria.matrix (area enclosedby inner membrane)mitochondrionATPAND6CO 2BIOLOGYView an animationof cellular respirationat ClassZone.com.energy2<strong>Energy</strong>-carryingmolecules transferenergy to Stage 2.STAGE 2: Electron Transport3<strong>Energy</strong>-carrying molecules fromglycolysis <strong>and</strong> the Krebs cycle enterStage 2 of cellular respiration.inner membraneenergy from glycolysisATPAND6O 2AND6H 2 OIdentify What are the reactants <strong>and</strong>products in cellular respiration?4ATP molecules are produced.Heat <strong>and</strong> water are releasedas waste products.114 Unit 2: <strong>Cells</strong>
Change language