Module 4 Notes
3-D Animation—Cellula r Respir ation
ATP synthesis-is driv en by the me tabolic br eakdown o f molecules such as glucose i n a pro cess known as cell respir ation
Aerobic r espir ation-Euk aryoti c animal cell/begins in the cyt osol and is comple ted in th e mitochondrion
Three s tages
1. In cytosol with gly colysis which spits sug ars into two smaller mol ecules
-two molecules of A TP are cons umed to phospho rylate the s ugar
-the sug ar is split
-NAD pick up electr on and h ydrogen atoms t o become N ADH
-free phosphat e groups are a dded
-then f our A TP molecules are made using these phosph ates
-substr ate lev el phosphorylati on
-for each gluc ose molecule, there is a net g ain of tw o ATP
-the two thr ee-carbo n molecules that e xit gly colysis, are p yruva te mole cules
-pyruv ate enter s the mi tochondrion and in to the mit ochondrial ma trix
-a multi-enzyme c omplex r emo ves the car bon fr om pyruv ate, for ming one molecule of c arbon dio xide
-the enzyme l inks the re maining two c arbon acetyl gr oup t o coenz yme a f orming acetyl-C oA
-one NADH molecule is f ormed during t his pro cess per pyruv ate molecule
-each glucose molecule le ads to tw o pyruv ates and so to ace tyl-CoA
2. citric acid cy cle
-still inside the mit ochondrial matr ix, a two c arbon acetyl-Co A compound joins a f our-carbon molecule t o
form citric acid -carbon co mpounds are b roken down and coenz yme a is recycled
-for every acetyl, two mol ecules of carbon dio xide are r eleased
-one A TP molecule is s ynthesized b y substrate lev el phosphorylation
-three NA DH and F ADH2 are gener ated (these c arry high-ener gy electro ns, which will next enter the electron tr ansfer chain wher e most o f the A TP is made)
3. electr on tra nsfer chain
-high-energy ele ctrons deli vered by electr on carriers, N ADH and F ADH2 flow down a chain of phosphorylation of ADP t o form A TP
-also called o xidative phosphorylation bec ause o xygen is indispensable f or this
-NADH and F ADH2 deposit their high-energy el ectrons a nd release p rotons -the electrons t ravel from c omplex one to f our
-as electrons m ove along the chain, pro tons are dr awn tow ards them only to b e pumped into the interme mbrane side, wher e they ar e concen trated
-prot ons then flow back th rough A TP syn thase
-prot ons moving down their gradient thr ough A TP synth ase provid e a motor f orce causing A TP syn thase to rotate and ther eby making A TP by o xidative phosphorylati on
-the final electr on acceptor at the end o t he electro n transf er chain is oxy gen and w ater is produ ced as a result
-the rem oval of el ectrons serv es as an essential si nk so electro ns and prot ons can c ontinue t o ent er the system
-the end result i s ATP that dr ives also activities and a nimals, plants, and other organisms
3-D Animation—Cellula r Respir ation
ATP synthesis-is driv en by the me tabolic br eakdown o f molecules such as glucose i n a pro cess known as cell respir ation
Aerobic r espir ation-Euk aryoti c animal cell/begins in the cyt osol and is comple ted in th e mitochondrion
Three s tages
1. In cytosol with gly colysis which spits sug ars into two smaller mol ecules
-two molecules of A TP are cons umed to phospho rylate the s ugar
-the sug ar is split
-NAD pick up electr on and h ydrogen atoms t o become N ADH
-free phosphat e groups are a dded
-then f our A TP molecules are made using these phosph ates
-substr ate lev el phosphorylati on
-for each gluc ose molecule, there is a net g ain of tw o ATP
-the two thr ee-carbo n molecules that e xit gly colysis, are p yruva te mole cules
-pyruv ate enter s the mi tochondrion and in to the mit ochondrial ma trix
-a multi-enzyme c omplex r emo ves the car bon fr om pyruv ate, for ming one molecule of c arbon dio xide
-the enzyme l inks the re maining two c arbon acetyl gr oup t o coenz yme a f orming acetyl-C oA
-one NADH molecule is f ormed during t his pro cess per pyruv ate molecule
-each glucose molecule le ads to tw o pyruv ates and so to ace tyl-CoA
2. citric acid cy cle
-still inside the mit ochondrial matr ix, a two c arbon acetyl-Co A compound joins a f our-carbon molecule t o
form citric acid -carbon co mpounds are b roken down and coenz yme a is recycled
-for every acetyl, two mol ecules of carbon dio xide are r eleased
-one A TP molecule is s ynthesized b y substrate lev el phosphorylation
-three NA DH and F ADH2 are gener ated (these c arry high-ener gy electro ns, which will next enter the electron tr ansfer chain wher e most o f the A TP is made)
3. electr on tra nsfer chain
-high-energy ele ctrons deli vered by electr on carriers, N ADH and F ADH2 flow down a chain of phosphorylation of ADP t o form A TP
-also called o xidative phosphorylation bec ause o xygen is indispensable f or this
-NADH and F ADH2 deposit their high-energy el ectrons a nd release p rotons -the electrons t ravel from c omplex one to f our
-as electrons m ove along the chain, pro tons are dr awn tow ards them only to b e pumped into the interme mbrane side, wher e they ar e concen trated
-prot ons then flow back th rough A TP syn thase
-prot ons moving down their gradient thr ough A TP synth ase provid e a motor f orce causing A TP syn thase to rotate and ther eby making A TP by o xidative phosphorylati on
-the final electr on acceptor at the end o t he electro n transf er chain is oxy gen and w ater is produ ced as a result
-the rem oval of el ectrons serv es as an essential si nk so electro ns and prot ons can c ontinue t o ent er the system
-the end result i s ATP that dr ives also activities and a nimals, plants, and other organisms
