<p> AP Biology Photosynthesis Questions and Standards</p><p>You may download this entire file in Microsoft Word Format, or you may preview the questions and standards by year through your web browser by selecting the appropriate year.</p><p>1982 1986</p><p>PHOTOSYNTHESIS QUESTION 1982: L. PETERSON/ECHS</p><p>Describe the similarities and differences between the biochemical pathways of aerobic respiration and photosynthesis in eukaryotic cells. Include in your discussion the major reactions, the end products, and energy transfers.</p><p>STANDARDS: 7 points Maximum for Photosynthesis section 7 points Maximum for Respiration section PHOTOSYNTHESIS: ___Conversion of light energy to chemical energy ___Fixation of CO2 ___Occurs in chloroplasts ___Split H2O (photolysis) ___Chlorophyll needed ___ATP in light reaction ___NADPH2 produced ___Anabolic (Constructive) ___Oxygen released LIGHT REACTION (Diagram and/or Discuss) ___Photosystem I & II ___Energy "input" (electron flow) ___Chemiosmotic DARK REACTION (CO2 FIXATION) ___Carboxylative phase ___Reductive phase ___Regenerative phase NET REACTION ___ENERGY + CO2 + H20 -> C6H12O6 = O2 ___"Uphill" Reaction - possess more free energy and/or stores 686,000 cal/mole glucose ___Coupling of light and dark reactions RESPIRATION ___Conversion of chemical energy to metabolic ___Release of CO2 ___Occurs in mitochondria ___Form H2O (reduction) ___Cytochromes needed ___ATP in oxidative phosphorylation ___NADH produced ___Catabolic (destructive) OXIDATIVE PHOSPHORYLATION (Diagram and/or Discuss) ___ETS (NAD, FAD, cytochromes) ___Energy "release" (electron flow) ___Chemiosmotic</p><p>___Glycolysis ___Krebs Cycle NET REACTION ___O2 + C6H12O6 -> CO2 + H2O + ENERGY ___"Downhill"Reaction - possess less free energy and/or releases 686,000 cal/mole glucose BONUS POINTS 3 points MAX ___Dark reaction is reverse of anaerobic glycolysis ___Both processes are complementary and/or supply materials for each other ___Thorough contrast of photosynthesis and cellular respiration </p><p>PHOTOSYNTHESIS QUESTION 1986: L. PETERSON/ECHS</p><p>Describe the light reactions of photosynthesis and, for both a C3 and a C4 plant, trace the path of a carbon dioxide molecule from the point at which it enters a plant to its incorporation into a glucose molecule. Include leaf anatomy and bio- chemical pathways in your discussion of each type of plant.</p><p>STANDARDS:</p><p>LIGHT REACHTIONS: Max. = 9 points __ Light required __ Light reactions on thylakoids (in grana) __ Cyclic and non-cyclic photophosphorylation/photosystems I & II __ H2O used/split/required __ Chlorophyll absorbs light __ Quality of light/color of light/wavelength of light must be correct __ Chlorophyll e-s excited/boosted to higher orbit __ Energy of e-s used to make ATP __ Chemiosmotic photophosphorylation/Mitchell hypothesis (proton gradient) __ Energy of e-s used to make NADPH+ __ ADP or NADP used __ Carrier molecules for ATP or NADPH+ production __ Electrons of P700 replaced <- P680 (PSI <- PSII) __ Electrons of P680 replaced <- H2O (PSII <- H2O) __ O2 comes from H2O __ O2 released to air __ Redox mentioned</p><p>C3 AND C4 ANATOMICAL AND BIOCHEMICAL PATHWAYS: Max. = 9 points __ CO2 enters through stomates __ CO2 diffuses from intercellular spaced into mesophyll __ Dark reaction/CO2 fixation in stroma (fluid) __ CO2 used/fixed/required __ Energy of ATP used __ Energy (e-s/Hs) of NADP reused __ C3 plants have palisade and spongy mesophyll __ C4 plants have functional mesophyll around bundle sheaths __ C4 plants have Kranz anatomy __ C4 plants have chloroplasts in bundle sheath cells __ C3 plants combine CO2 with RuBP __ C4 plants combine CO2 with PEP __ C4 plants use CAM pathway __ Steps in PEP -> 4-C -> PEP __ C4 plants send 4-C to bundle sheath __ C3 and C4 plants put CO2 into Calvin cycle -> glucose __ Steps in Calvin cycle __ Mention of C3, C4 pathway enzymes</p>