Photosynthesis The Calvin Cycle Life from Air AP

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Photosynthesis: The Calvin Cycle Life from Air AP Biology 2007 -2008

Photosynthesis: The Calvin Cycle Life from Air AP Biology 2007 -2008

Whoops! Wrong Calvin… The Calvin Cycle AP Biology 1950 s | 1961

Whoops! Wrong Calvin… The Calvin Cycle AP Biology 1950 s | 1961

Remember what it means to be a plant… § Need to produce all organic

Remember what it means to be a plant… § Need to produce all organic molecules necessary for growth u carbohydrates, lipids, proteins, nucleic acids § Need to store chemical energy (ATP) produced from light reactions in a more stable form u that can be moved around plant u saved a rainy day glucose + oxygen carbon + for water + energy u dioxide 6 CO 2 + 6 H 2 O + light C 6 H 12 O 6 + 6 O 2 energy AP Biology

Light reactions § Convert solar energy to chemical energy ATP u ATP energy u

Light reactions § Convert solar energy to chemical energy ATP u ATP energy u NADPH reducing power § What can we do now? build stuff !! AP Biology photosynthesis

How is that helpful? § Want to make C 6 H 12 O 6

How is that helpful? § Want to make C 6 H 12 O 6 synthesis u How? From what? What raw materials are available? u CO 2 NADPH carbon fixation NADP C 6 H 12 O 6 AP Biology reduces CO 2 NADP

From CO 2 C 6 H 12 O 6 § CO 2 has very

From CO 2 C 6 H 12 O 6 § CO 2 has very little chemical energy u fully oxidized § C 6 H 12 O 6 contains a lot of chemical energy u highly reduced § Synthesis = endergonic process u put in a lot of energy § Reduction of CO 2 C 6 H 12 O 6 proceeds in many small uphill steps each catalyzed by a specific enzyme u using energy stored in ATP & NADPH u AP Biology

From Light reactions to Calvin cycle § Calvin cycle u chloroplast stroma § Need

From Light reactions to Calvin cycle § Calvin cycle u chloroplast stroma § Need products of light reactions to drive synthesis reactions ATP u NADPH u ATP thylakoid AP Biology stroma

C Calvin cycle 1 C C C 3. Regeneration C C C of Ru.

C Calvin cycle 1 C C C 3. Regeneration C C C of Ru. BP starch, sucrose, cellulose & more ribulose bisphosphate 3 ATP H H H | | | C–C–C AP Biology C C C C CO 2 5 C Ru. Bis. Co glyceraldehyde-3 -P G 3 P 3 C C 6 NADP 6 C PGA phosphoglycerate C C C 3 C C C C C 6 ATP 2. Reduction 6 NADPH 1. Carbon fixation C C C ribulose bisphosphate carboxylase 3 ADP used to make glucose C=C=C 5 C C C 3 C 6 ADP H | H |

Remember G 3 P? glycolysis glucose C-C-C-C 2 ATP 2 ADP fructose-1, 6 b.

Remember G 3 P? glycolysis glucose C-C-C-C 2 ATP 2 ADP fructose-1, 6 b. P P-C-C-C-P DHAP P-C-C-C G 3 P glyceraldehyde 3 -phosphate C-C-C-P 2 NAD+ 2 4 ADP AP Biology Photosynthesis pyruvate C-C-C 4 ATP

To G 3 P and Beyond! § Glyceraldehyde-3 -P To G 3 P and

To G 3 P and Beyond! § Glyceraldehyde-3 -P To G 3 P and beyond! end product of Calvin cycle u energy rich 3 carbon sugar u “C 3 photosynthesis” u § G 3 P is an important intermediate § G 3 P glucose carbohydrates lipids phospholipids, fats, waxes amino acids proteins nucleic acids DNA, RNA AP Biology

Ru. Bis. Co § Enzyme which fixes carbon from air ribulose bisphosphate carboxylase u

Ru. Bis. Co § Enzyme which fixes carbon from air ribulose bisphosphate carboxylase u the most important enzyme in the world! u § it makes life out of air! definitely the most abundant enzyme It’s not easy u I’m green with envy! AP Biology being green!

Accounting § The accounting is complicated u 3 turns of Calvin cycle = 1

Accounting § The accounting is complicated u 3 turns of Calvin cycle = 1 G 3 P u 3 CO 2 1 G 3 P (3 C) u 6 turns of Calvin cycle = 1 C 6 H 12 O 6 (6 C) u 6 CO 2 1 C 6 H 12 O 6 (6 C) u 18 ATP + 12 NADPH 1 C 6 H 12 O 6 u AP Biology any ATP left over from light reactions will be used elsewhere by the cell

Photosynthesis summary § Light reactions produced ATP u produced NADPH u consumed H 2

Photosynthesis summary § Light reactions produced ATP u produced NADPH u consumed H 2 O u produced O 2 as byproduct u § Calvin cycle consumed CO 2 u produced G 3 P (sugar) u regenerated ADP u regenerated NADP u AP Biology ADP NADP

Light Reactions light ATP + NADPH + O 2 energy H 2 O +

Light Reactions light ATP + NADPH + O 2 energy H 2 O + H 2 O sunlight Energy Building Reactions NADPH ATP AP Biology O 2 § produces ATP § produces NADPH § releases O 2 as a waste product

Calvin Cycle CO 2 + ATP + NADPH C 6 H 12 O 6

Calvin Cycle CO 2 + ATP + NADPH C 6 H 12 O 6 + ADP + NADP CO 2 ADP NADP Sugar Building Reactions NADPH ATP AP Biology sugars § builds sugars § uses ATP & NADPH § recycles ADP & NADP § back to make more ATP & NADPH

Putting it all together light CO 2 + H 2 O + energy C

Putting it all together light CO 2 + H 2 O + energy C 6 H 12 O 6 + O 2 H 2 O CO 2 sunlight ADP Energy NADP Building Reactions Sugar Building Reactions NADPH ATP AP Biology O 2 sugars Plants make both: § energy § ATP & NADPH § sugars

even though this equation is a bit of a lie… it makes a better

even though this equation is a bit of a lie… it makes a better story Energy cycle sun Photosynthesis light CO 2 + H 2 O + energy C 6 H 12 O 6 + O 2 plants CO 2 H 2 O glucose animals, plants ATP C 6 H 12 O 6 + O 2 energy + CO 2 + H 2 O Cellular Respiration AP Biology The Great Circle of Life, Mufasa! ATP O 2

Summary of photosynthesis 6 CO 2 + 6 H 2 O + light C

Summary of photosynthesis 6 CO 2 + 6 H 2 O + light C 6 H 12 O 6 + 6 O 2 energy § § § § § Where did the CO 2 come from? Where did the CO 2 go? Where did the H 2 O come from? Where did the H 2 O go? Where did the energy come from? What’s the energy used for? What will the C 6 H 12 O 6 be used for? Where did the O 2 come from? Where will the O 2 go? What else is involved…not listed in this equation? AP Biology

Supporting a biosphere § On global scale, photosynthesis is the most important process for

Supporting a biosphere § On global scale, photosynthesis is the most important process for the continuation of life on Earth u each year photosynthesis… § captures 121 billion tons of CO 2 § synthesizes 160 billion tons of carbohydrate u AP Biology heterotrophs are dependent on plants as food source for fuel & raw materials

The poetic perspective… § All the solid material of every plant § was built

The poetic perspective… § All the solid material of every plant § was built by sunlight out of thin air All the solid material of every animal was built from plant material air AP Biology sun Then all the plants, cats, dogs, elephants & people … are really particles of air woven together by strands of sunlight!

If plants can do it… You can learn it! Ask Questions!! AP Biology 2007

If plants can do it… You can learn it! Ask Questions!! AP Biology 2007 -2008