Presentation is loading. Please wait.

Presentation is loading. Please wait.

Biochemistry Bioenergetics: How the body converts food to energy.

Similar presentations


Presentation on theme: "Biochemistry Bioenergetics: How the body converts food to energy."— Presentation transcript:

1 Biochemistry Bioenergetics: How the body converts food to energy

2 Bioenergetics  Metabolism  Metabolism: The sum of all Chemical Reactions involved in maintaining the dynamic state of the cell –Catabolism –Catabolism - breaking down of molecules to supply energy –Anabolism –Anabolism - synthesis of molecules –Biochemical Pathway –Biochemical Pathway - a series of consecutive chemical reactions

3 Common Catabolic Pathway Conversion of FOOD to ATP:  FOOD produces C 4 and C 2 fragments  C 4 and C 2 fragments enter Citric Acid Cycle  CO 2, NADH, FADH 2, are produced  Electron Transport  Electron Transport produces ATP

4 O2O2 O2O2 Citric Acid Cycle C2C2C2C2 C2C2C2C2 C2C2C2C2 CO 2 C4C4C4C4 C4C4C4C4 NADH FADH 2 ATP H2OH2O outer membrane inner membrane e - transport

5 Cells and Mitochondria Components of a typical cell:  nucleus - replication of cell begins here  lysosomes - remove damaged cellular components  Golgi bodies - package and transport proteins  organelles - specialized structures with specific function  mitochondria - common catabolic pathway

6 Cells and Mitochondria

7

8 Mitochondria  Mitochondria –Two membranes –Common Catabolic Pathway Crista –Enzymes located in folds or “Crista” Protein Gates –Transport thru the inner membrane occurs with the help of Protein Gates

9 Mitochondrion

10 Common Catabolic Pathway 2 Parts:  Citric Acid Cycle –or Tricarboxylic Acid Cycle –or TCA cycle –or Kreb’s Cycle  Oxidative Phosphorylation –or Electron Transport –or Respiratory Chain 1 2

11 Compounds - ADP  Adenosine diphosphate (ADP)

12 Compounds - ATP  AMP, ADP, ATP High energy phosphate anhydride bonds triphosphate

13 Compounds - ATP  ATP –We make about 88 lbs. of ATP a day!!! –Used for: »muscle contraction »nerve signal conduction »biosynthesis

14 Fig. 26.6, p.651

15 Compounds - Redox  NAD + and FAD –Oxidizing agents –Actually coenzymes –Contain an ADP core (part of R or R’) NAD + FAD

16 Compounds - Redox  NAD + is converted to NADH Oxidized form Reduced form to ET

17 Compounds - Redox  FAD is converted to FADH 2 Oxidized form Reduced form to ET

18 Compounds Acetyl  The Acetyl carrying group - Acetyl coenzyme A  Carrying handle is Pantothenic Acid and Mercaptoethylamine

19 Coenzyme A

20 4C3C2C

21 Fig. 26.8, p.652

22

23 Citric Acid Cycle  Acetyl CoA contains a 2 carbon fragment that is carried into the Citric Acid Cycle  Also called the: –Tricarboxylic Acid Cycle –TCA Cycle –Kreb’s Cycle  Acetyl group is split out as CO 2 C5C5 CO 2 C4C4 C4C4 C6C6 C2C2

24 Citric Acid Cycle  Step 1 –oxaloacetate will show up in last step –acetyl CoA is the THIO ESTER of acetic acid (CoA is Co Enzyme A)

25 Citric Acid Cycle  Step 1B –citrate or citric acid produced –citrate has 6 C (How many acid groups?)

26 Fig. 26.8, p.652

27 Citric Acid Cycle  Step 2 –dehydration to cis-Aconitate –hydration to isocitrate –enzymes required for each Rx

28 Fig. 26.8, p.652

29 Citric Acid Cycle  Step 3 –oxidation and decarboxylation –CO 2 is from the ???

30 Fig. 26.8, p.652

31 Citric Acid Cycle  Step 4 –Where did the CO 2 come from???

32 Fig. 26.8, p.652

33 Citric Acid Cycle  Step 5 –GTP is Guanosine triphosphate (as good as ATP!)

34 Fig. 26.8, p.652

35 Citric Acid Cycle  Step 6 –Oxidation with FAD –Fumaric Acid is trans-Fumaric Acid –Barbiturate is an inhibitor of Succinate dehydrogenase

36 Fig. 26.8, p.652

37 Citric Acid Cycle  Step 7 –hydration reaction –fumarase is enzyme

38 Citric Acid Cycle  Step 8 –oxidation using NAD + –product is oxaloacetate!

39 Fig. 26.8, p.652

40 Electron (and H + ) Transport  End products of the Citric Acid Cycle Reduced (or spent) Coenzymes –NADH –FADH 2  Carry H+ and e- and yield energy when combining with oxygen: 4 H e - + O 2 2 H 2 O

41 Electron (and H + ) Transport  Many Enzymes are involved in ET  Enzymes are imbedded in inner membrane of the mitochondria  Enzymes are in a particular sequence –each accepts electrons –increasing affinity for electrons  Final acceptor of electrons is molecular O 2 to make water O2O2

42 Fig , p.656

43 p=F09BC040A0B953F8&playnext=1&playnext_from=PL&index=10 Electron Transport chain - youtube

44 Electron (and H + ) Transport  Many Enzymes are involved in Oxidative Phosphorylation 2 H e - + 1/2 O 2 H 2 O Flavo- protein Lipid bilayer FeS protein Q enzyme b b c1c1 c a a3a3 ATPase cytochromes O2O2O2O2 NADHNAD + FADH 2 FAD ATP 2 H + 2 ATP overall 2 ATP produced 3 ATP overall 3 ATP produced O 2-

45 The Energy Yield from a C 2  Each NADH produces 3 ATP  Each FADH 2 produces 2 ATP (Each pair of H + produces 1 ATP )  For each C 2 unit (acetyl CoA) we produce... –1 GTP directly (same as 1 ATP) from step 5 TCA –3 NADH in ET (3 x 3 = 9 ATP) Indirect –1 FADH 2 in ET (1 x 2 = 2 ATP) Indirect For a total of ATP (and some waste CO 2 ) $ Indirect (from ET)

46 Conversion of ATP How does the body utilize this Chemical Energy?  Conversion to Other Forms –biosynthesis  Electrical Energy –ion gradients (K +, Na + )  Mechanical Energy –muscle contraction  Heat Energy –maintain 37 o C or 98.6 o F

47 Muscle Contraction Chemical Energy converted to Mechanical Energy:  Thick (myosin) and thin (actin) filaments  Hydrolysis of ATP causes the interaction of the filaments (muscle contraction) contraction


Download ppt "Biochemistry Bioenergetics: How the body converts food to energy."

Similar presentations


Ads by Google