Ch 7 Cellular Respiration
7.1 Glycolysis & Fermentation
MMMMmmm.... You eat lunch… Digest its macromolecules...into How do you get the ENERGY out?
Cellular Respiration— What is it? Breaking down organic molecules (from food!) & Making ATP For cell’s chem reactions Make ATP by breaking down org molec Use ATP to do cell’s work
Opposite of Photosynthesis— Flip the equation!! Cell Resp: 6O2 + C6H12O6 6CO2 + 6H2O + ATP you can’t “make” sunlight, so you make ATP instead!! Glucose + 6O2 –enzymes 6CO2 + 6H2O + ATP
3 Main Processes Glycolysis Aerobic: Cell Respiration Anaerobic: Fermentation Oxygen NO Oxygen 1. Gly- org cmpds 3C pyruvic acid, little ATP, NADH Anaerobic 2. Aerobic pyr acid broken down, NADH used, make lots ATP 3. Anaerobic Fermentation
Fermentation (without oxygen) Aerobic Respiration: in mitochondria! Glycolysis: In cell’s cytoplasm Glucose Glycolysis Krebs cycle Electron transport Fermentation (without oxygen) Alcohol or lactic acid Glucose Acetyl CoA 6C & 4C molecules Pyruvic Acid Anaerobic Respiration: In cell’s cytoplasm No ATP but it does allow for more glycolysis to take place Ethanol & CO2 (plants, yeast) Or lactic Acid (animals)
1. Glycolysis In the cytosol No Oxygen! Basics: break glucose, Make: pyruvic acid, 2 net ATP, & NADH (e- carrier) in the cytoplasm. It does not require oxygen. Glucose + Phosphates (from ATP); split in ½ G3P (same as in calvin cycle) + 2 P, NAD+ NADH (e- acceptor); P removed to make ATPs; 2 net ATP
Glycolysis
2. Aerobic Respiration Only If Oxygen is available Break Pyruvic acid, lots of reactions (another cycle), lots of ATP made More on this in 7.2!
3. Anaerobic Respiration Fermentation
Fermentation (Anaerobic Respiration) Breakdown of Pyruvic Acid NO OXYGEN required AFTER Glycolysis (bc need pyr. acid) DOES NOT Make ATP but it does make NAD so glycolysis can still happen pyruvic acid w/o use of oxygen. & regenerate NAD+ for reuse in glycolysis (to make ATP) AFTER Glycolysis does not produce any ATP.
Fermentation Lactic Acid Fermentation Alcoholic Fermentation Muscle Cells (ouch! The burn!!) Pyruvic Acid Lactic Acid NAD also made, goes back to do more glycolysis Yeast, bacteria, plants **ethanol that’s put in gas is from corn! Pyruvic acid Ethanol + carbon dioxide NAD also, for more glycolysis Other uses: Yogurt, bread, beer, wine...it’s all made from fermentation!
What’s the difference? Similarities?
HW Review! p. 136 #1-3,7
7.2 Aerobic Respiration
2. Aerobic Respiration C6H12O6 + 6 O2 → 6 H2O + 6 CO2 + 38 ATP Must have oxygen Make LOTS of ATP within the mitochondria Mitochondria Link Reaction Kreb’s Cycle Electron Transport Chain
Mitochondria...Draw It! Inner & Outer Membranes Cristae Matrix outer and inner membrane matrix: dense solution enclosed by inner membrane cristae: the folds of the inner membrane that house the electron transport chain and ATP synthase
Structure of Mitochondrion
Aerobic Respiration 3 Main Steps: Mitochondria Link Reaction Kreb’s Cycle Electron Transport Chain
Link Reaction: Pyr Acid into Mito Link Reaction: Pyr Acid into Mito. Matrix Acetyl CoA (loses a C as CO2; NADH made...goes to ETC)
Conversion of Pyruvic Acid: you do NOT need to know the details! NAD+ NADH + H+ Pyruvic Acid C Acetyl-CoA C CO2 C CoA CoA Kreb's Cycle Citric Acid C Oxaloacetic Acid C NAD+ NADH + H+ NADH + H+ CO2 C NAD+ Ketoglutaric Acid C Malic Acid C NAD+ NADH + H+ Succinic Acid C CO2 C FADH2 ATP ADP + P FAD
Hans! (Krebs)
2. KREBS Cycle: Acetyl CoA broken down; make CO2, H+, ATP, NADH, FADH2 (another e- carrier) in Mit Matrix 1 glucose made every 2 turns 2 NADH 8 NADH 2 FADH2 2 2
6C 4C 4C 4C
Pair-Share… Summarize the Krebs Cycle
3. Electron Transport Chain REVIEW--Up to this point: 4 ATP (2 from glycolysis, 2 from Krebs) 10 NADH (2 from glycolysis, 2 from link, 6 from Krebs) 2 FADH2 (from Krebs) Go to E.T.C., 34 ATP made
3. Electron Transport Chain ETC is lots of proteins in cristae folds that pass e-s & energy, H+ ATP Synthase (enzyme, at end of ETC ) Pump H+ from space to matrix, makes ATP OXYGEN: final e- acceptor, end of ETC Makes WATER!! (remember the equation?) E- carriers: NADH and FADH2 10 NADH 30 ATP 2 FADH2 4 ATP Ox = final e-acceptor at end ETC; form water (stops if no ox b/c e- build up and don’t get passed) E- carriers
The E.T.C. Electron Transport Hydrogen Ion Movement Channel ATP Production ATP synthase Channel Inner Membrane Matrix Intermembrane Space
Electron Transport Chain’s the Last Step! (Thank goodness, right?! )
Energy Summary
p. 144 1-6,8
We’ll do the rest of this when I return We’ll do the rest of this when I return...do the Ch Review and hopefully I’ll be back tomorrow!
p.146 1,5,7,9,11,12,16,18,20
p.139
p. 147 P.147
chloroplast sunlight Thylakoid chlorophyll oxygen WATER Energy-carrying molecules transferred to light-independent reactions 6-C sugar (glucose) Light-indep. Rxns (Calvin Cycle) CO2 from atmosphere
WHY do your cells need Oxygen? oxygen must accept the final e- If not, it stops the ETC!
Summary of Cell Respiration 1ST STEP? Glycolysis- converts glucose to pyruvic acid, only makes a little ATP Aerobic- pyruvic acid CO2 & H2O ONLY in presence of oxygen Creates A LOT of ATP
Comparing Photosynthesis & Cell Resp. graphic organizer
Chemical Equation C6H12O6 + 602 6CO2 + 6H2O + ATP What's this?
Light reactions and Calvin Cycle
Harvesting Chemical Energy Cell Respiration Process in which cells make ATP by breaking down organic compounds This is done in both heterotrophs and autotrophs