Cellular Respiration ATP 2009-2010

Harvesting energy stored in food Cellular respiration breaking down food to produce ATP Occurs in cytoplasm & mitochondria using oxygen “aerobic” respiration involves digesting glucose but could be other sugars, fats, or proteins ATP food O2 Movement of hydrogen atoms from glucose to water glucose + oxygen  energy + carbon dioxide + water C6H12O6 6O2 36ATP 6CO2 6H2O  +

What do we need to make energy? The “Furnace” for making energy mitochondria Fuel food: carbohydrates, fats or proteins Helpers oxygen enzymes Product ATP Waste products carbon dioxide then used by plants water Make ATP! Make ATP! All I do all day… And no one even notices! food ATP enzymes CO2 H2O O2

ATP – an energy rich molecule

Using ATP to do work? Can’t store ATP too unstable only used in cell that produces it only short term energy storage carbohydrates & fats are long term energy storage ATP Adenosine Triphosphate work Adenosine Diphosphate ADP A working muscle recycles over 10 million ATPs per second Whoa! Pass me the glucose & oxygen!

Mitochondria are in Eukaryotes!! animal cells plant cells

{ { { ATP A Body’s Energy Budget make energy eat food synthesis 1 make energy • energy needed even at rest • activity • temperature control { ATP eat food • growth • reproduction • repair { 2 synthesis (building) • glycogen (animal starch) • fat { 3 storage

Cellular Respiration Overview Cellular Respiration Overall Equation 6O2 + C6H12O6  6CO2 + 6H2O + Energy Three Stages Glycolysis Kreb’s Cycle Electron Transport Chain The Main form of Energy produced = ATP

STAGES OF CELLULAR RESPIRATION Respiration occurs in three main stages High-energy electrons carried by NADH ELECTRON TRANSPORT CHAIN GLYCOLYSIS KREBS CYCLE Cytoplasmic fluid Mitochondrion

1. Glycolysis Glucose Breakdown/split Glyco = lysis = Occurs in the cytoplasm of the cell Molecules of GLUCOSE are broken down into 2 molecules of Pyruvic Acid. Cell must use (invest) 2 ATP Produces Energy Carrier Molecules 4 ATP 2 NADH

Glycolysis Glucose Pyruvic Acid Pyruvic Acid To the Electron Transport Chain

The “Mighty” Mitochondria The mitochondria is the organelle where the final stages of cellular respiration occurs. Kreb’s Cycle Electron Transport Chain Cells that use a lot of energy have high numbers of mitochondria. Example: Muscle cells in the heart!!

One glucose molecule completes two turns of the Kreb’s Cycle Aerobic Process = Only if oxygen is present!! Occurs in the MATRIX of the mitochondria Pyruvic Acid from Glycolysis enters to form 1 ATP 3 NADH 1 FADH2 CO2 (which is released when we exhale!!) AKA….Citric Acid Cycle One glucose molecule completes two turns of the Kreb’s Cycle

3. Electron Transport Chain Chapter 9-2 Energy carrier molecules produced during Glycolysis and the Kreb’s Cycle enter the ETC NADH FADH2 Occurs in the folds of the Inner Membrane of the Mitochondria (Cristae) The electrons are passed down a chain of proteins until they reach the final electron acceptor…..oxygen! So this step is aerobic (requires oxygen) The ETC produces 32 ATP and H2O

Cellular Respiration Flowchart Section 9-2 32 ATP Glucose (C6H1206) + Oxygen (02) 2 ATP Glycolysis Krebs Cycle Electron Transport Chain Carbon Dioxide (CO2) + Water (H2O) 2 ATP Total 36 ATP

What if oxygen is missing? No oxygen available = can’t complete aerobic respiration Anaerobic respiration also known as fermentation alcohol fermentation lactic acid fermentation no oxygen or no mitochondria (bacteria) can only make 2 ATP large animals cannot survive yeast bacteria

What happens if NO OXYGEN is available?? The Kreb’s Cycle and Electron Transport Chain can’t function!! These are anaerobic conditions!!

O2 Fermentation The cell can use Fermentation instead!! Occurs in the Cytoplasm Just like glycolysis!! A series of reactions that convert NADH (from glycolysis) back into NAD allowing glycolysis to keep producing a small amount of ATP

Pyruvic Acid + NADH  alcohol + CO2 + NAD+ 2 Types of Fermentation 1. Alcoholic Fermentation Yeasts use this process to form ethyl alcohol and carbon dioxide as waste products. This causes bread dough to rise This is how some alcoholic beverages are made glucose  2ATP + CO2+ alcohol Pyruvic Acid + NADH  alcohol + CO2 + NAD+

2. Lactic Acid Fermentation Occurs in bacteria (unicellular organisms) This is how cheese, yogurt, and pickles are made. Occurs in muscles during rapid exercise When your body runs out of oxygen your muscle cells must produce some ATP using fermentation and glycolysis Lactic Acid build-up causes muscle soreness or burning after intense activity. Pyruvic Acid + NADH  lactic acid + NAD+

Glycolysis: Glucose  2 Pyruvic Acid Fermentation Summary Glycolysis: Glucose  2 Pyruvic Acid Fermentation: 2 Pyruvic Acid  ? or ? Alcohol Lactic Acid