http://www.clickatutor.com/mitochondria.jpg Cellular Respiration Campbell Chapter 9 Slide shows modified from: Glenbrook High School AP site http://gbs.glenbrook.k12.il.us/Academics/gbssci/bio/apbio/Index/index.htm & Dr. Chuck Downing http://gohs.tvusd.k12.ca.us/TeacherWebs/Science/CDowning/default.aspx
In the last chapter green plants used ________________ http://www.inclusive.co.uk/downloads/images/pics2/tree.gif AUTOTROPHS ___________ use energy from sunlight or chemicals to make their own food In the last chapter green plants used ________________ trap energy from __________ and make ______________ PHOTOSYNTHESIS sunlight food (glucose) http://206.173.89.42/REALTYWITHALOHA_COM/piphoto/funny%20sun%20with%20sunglasses.gif
In this chapter we will learn how ______________ Image from: http://ag.ansc.purdue.edu/sheep/ansc442/Semprojs/2003/spiderlamb/eatsheep.gif In this chapter we will learn how ______________ get their energy by consuming other organisms. HETEROTROPHS GLUCOSE We get our energy from the __________ plants made during _______________ when we eat plants or eat animals that ate the plants. PHOTOSYNTHESIS http://www.cibike.org/Eating.htm
In this chapter, we will learn how this glucose is ____________ by organisms and the _______ is stored as _______ broken down energy ATP What kind of organisms do this?
ALL LIVING THINGS NEED ENERGY! All organisms burn glucose for fuel Animals (Including humans) plants bacteria fungi
PHOTOSYNTHESIS CELLULAR RESPIRATION 6 CO2 6 H2O C6H12O6 6O2 C6H12O6 ___________ + _________ + ___________ →_______________ + __________ 6 H2O C6H12O6 6O2 CELLULAR RESPIRATION C6H12O6 6 CO2 _____________ + _________ →________ + __________ + __________ ______________________________________________________________ 6O2 6 H2O The two equations are exact opposites!
REMEMBER: OIL RIG OXIDATION REDUCTION http://www1.istockphoto.com/file_thumbview_approve/777814/2/istockphoto_777814_oil_bonus_pack.jpg REMEMBER: OIL RIG OXIDATION REDUCTION Is Loss of electrons Is Gain of electrons Remove H Add H Releases energy Stores energy Exergonic Endergonic OXIDATION Loss of hydrogen atoms Gain of hydrogen atoms Energy REDUCTION
slowly in ________________. many steps CELLULAR RESPIRATION happens __________ in ________________. If all the energy was released in one step… most would be lost as ____________________! slowly many steps light and heat See why cells use cellular respiration http://plato.acadiau.ca/COURSES/comm/g5/Fire_Animation.gif
ELECTRON TRANSPORT CHAIN Prevents energy release in 1 explosive step Allows energy to be released slowly in steps and captured as ATP Electron route: food → NADH → ETC → oxygen
MITOCHONDRIA = cell power plant Surrounded by ___________ membrane Outer membrane & Inner membrane (called _______________ ) Space between inner membrane & outer membrane = ____________________ Space inside cristae folds = _________________ DOUBLE CRISTAE INTERMEMBRANE SPACE MATRIX
HIGH ENERGY ELECTRON CARRIERS FAD → FADH2 NAD+ → NADH
The first step in cellular respiration = _______________ happens in the ________________ outside the mitochondria occurs _________________________ GLYCOLYSIS CYTOPLASM with or without oxygen See glycolysis movie
PREPARATORY PHASE (energy investment) Steps – A fuel molecule is energized, using ATP. Glucose 1 3 Details of glycolysis Step 1 Glucose-6-phosphate 2 Fructose-6-phosphate 3 Fructose-1,6-diphosphate Step A six-carbon intermediate splits into two three-carbon intermediates. 4 4 Glyceraldehyde-3-phosphate (G3P) Arraugh! Like, this is way hard! ENERGY PAYOFF PHASE 5 Step A redox reaction generates NADH. 5 1,3-Diphosphoglyceric acid (2 molecules) 6 Steps – ATP and pyruvic acid are produced. 3-Phosphoglyceric acid (2 molecules) 6 9 7 2-Phosphoglyceric acid (2 molecules) 8 2-Phosphoenolpyruvate (2 molecules) 9 Pyruvic acid (2 molecules per glucose molecule)
Glycolysis (GLYKOS = ________ LYSIS= ___________ ) Requires ____________to get it started. sweet Split apart ENERGY
SUBSTRATE LEVEL PHOSPHORYLATION = using energy from breaking a chemical bond to add a P directly from a phosphorylated molecule to ADP without a proton gradient MITOCHONDRION
PYRUVIC ACID MOVES TO NEXT STEP IF THERE IS NO OXYGEN (______________) IF THERE IS OXYGEN (_____________) = ANAEROBIC = AEROBIC
Cellular respiration Kreb’s Cycle: mitochondrial matrix; pyruvate → CO2 NADH made Electron Transport Chain: cristae; NADH & FADH2 donate electrons → oxygen Glycolysis: cytosol; glucose → pyruvate
Pyruvate is transported into mitochondrion and Acetyl CoA produced For each pyruvate converted into acetyl CoA 1 molecule of CO2 is released; NAD+ ---> NADH; Coenzyme A (from B vitamin) Krebs Cycle Animation-
Kreb’s Cycle = Citric Acid Cycle Krebs Cycle Animation OAA CITRIC ACID
Kreb’s Cycle Oxaloacetate (OAA) combines with 2 C’s from Acetyl CoA to make Citric acid CoA recycles 2 C atoms from pyruvate → exit as CO2 For each pyruvate that enters: 2 CO2 released 3 NAD+ reduced to 3 NADH; 1 FAD+ reduced to 1 FADH2 (riboflavin, B vitamin); 1 ATP molecule
Electron transport chain
Why don't both electron carriers make the same amount of ATP?
More on Making ATP 3 places in the chain make ATP NADH FADH2 Electrons from NADH start “higher” in the waterfall, so they generate more ATP than FADH2 electrons, which start “lower” in the waterfall and miss one ATP-generating step.
Electron transport chain ETC includes Cytochromes Ubiquinone (Q) NADH & FADH2 pass electrons pass down ETC Energy from moving electrons concentrates H+ ions in __________________ ________________: harnesses the flow of H+ back into the matrix make ATP (oxidative phosphorylation) ________ is final electron acceptor → ________ intermembrane space ATP synthase H2O Oxygen
Cellular Respiration Grand Total Glycolysis: →2 ATP (substrate-level phosphorylation) Kreb’s Cycle:→ 2 ATP (substrate-level phosphorylation) Electron transport & oxidative phosphorylation: 2 NADH (glycolysis) → 6ATP 2 NADH (acetyl CoA) →6ATP 6 NADH (Kreb’s) → 18 ATP 2 FADH2 (Kreb’s) → 4 ATP 38 TOTAL ATP from 1 molecule of glucose (-2 ATP to transport 2 pyruvate into mitochondria) NET of 36 ATP
WHAT IF THERE IS NO OXYGEN? IF THERE IS OXYGEN (_____________) = ANAEROBIC = AEROBIC
Related metabolic processes Fermentation: alcohol~ pyruvate →ethanol lactic acid~ pyruvate → lactate
ALCOHOLIC FERMENTATION _______ +_____ →__________ + ______ + _____ PYRUVIC ACID ALCOHOL CO2 NAD+ Happens when yeast makes bread dough rise CO2 bubbles make air spaces in bread Alcohol evaporates during cooking http://www.deliciousdelicious.com/archives/herb%20bread%201.jpg
ALCOHOLIC FERMENTATION _______ +_____ →__________ + ______ + _____ PYRUVIC ACID ALCOHOL CO2 NAD+ Used to make alcoholic beverages http://www.firstpath.com/images/alcohol.jpg
LACTIC ACID FERMENTATION _______ +_____ →______________ + ________ PYRUVIC ACID LACTIC ACID NAD+ Happens in muscles during exercise when body can’t get oxygen to tissues fast enough. Lactic acid builds up in muscles causing soreness http://www.miranda.com/library.en/Images/Pictures/girls-runners.jpg
LACTIC ACID FERMENTATION _______ +_____ →______________ + ________ PYRUVIC ACID LACTIC ACID NAD+ Happens when bacteria are used to make foods and beverages like yogurt, cheese, buttermilk, sauerkraut, kimchi http://chronicle.augusta.com/images/headlines/032200/DANNON_YOGURT.jpg http://www.reillydairy.com/natural_cheese.html
WHY DO FERMENTATION? WHY NOT JUST KEEP MAKING ATP USING GLYCOLYSIS? WITHOUT OXYGEN, PYRUVIC ACID ___________ and all the _______ carriers get full. Eventually glycolysis will builds up NAD+ NAD+
→ → FERMENTATION HAPPENS so cells can ____________________ PYRUVIC ACID _______ +_____ →__________ + ______ + _____ CO2 NAD+ ALCOHOL → NAD+ LACTIC ACID ______ → You get the NAD+ carriers back FERMENTATION HAPPENS so cells can ____________________ needed to keep glycolysis going REGENERATE the NAD+
FACULTATIVE ANAEROBES __________________________ = organisms that can make ATP using either fermentation or cellular respiration Ex: yeast and many bacteria With oxygen pyruvate → Krebs cycle Without oxygen → fermentation FACULTATIVE ANAEROBES
Beta oxidation= Organisms can use a variety of molecules for fuel __________________= breakdown of fatty acids into 2 carbon fragments that enter Krebs cycle as acetyl CoA 1 g of fat → twice as much ATP as 1 g of carbohydrate Beta oxidation=
Evolutionary Significance Most widespread metabolic pathway… suggests ancient prokaryotes probably used glycolysis to make ATP before oxygen was present Earliest fossil bacteria present 3.5 billion years ago but large amounts of oxygen not present until 2.7 billion years ago Glycolysis happens in cytoplasm without membrane bound organelles suggests it was found in early prokaryotic cells since eukaryotes appeared 1 billion years after prokaryotes (Endosymbiotic theory)
VOCAB OVERLOAD ?
CHEMIOSMOSIS = Generation of ATP from a proton gradient. It occurs in all living things Chloroplasts do it to make ATP in light reactions Mitochondria do it to make ATP following ETC Prokaryotes create gradient across cell membrane to make ATP to pump nutrients & waste and move flagella http://student.ccbcmd.edu/~gkaiser/biotutorials/energy/atpsynthase_il.html
PHOTOPHOSPHORYLATION = Using hydrogen gradient generated by thylakoid membrane during the light reactions of photosynthesis to make ATP CHLOROPLAST
OXIDATIVE PHOSPHORYLATION = using proton gradient created by electron transport chain in cristae membrane to make ATP MITOCHONDRION
SUBSTRATE LEVEL PHOSPHORYLATION = using energy from breaking a chemical bond to add a P directly from a phosphorylated molecule to ADP without a proton gradient MITOCHONDRION