Cellular Respiration A process performed in the cells of ALL LIVING THINGS to release the energy in the bonds of food and allow the cell to create ATP energy *Can break down carbohydrates, lipids, and proteins.

2. Aerobic Respiration Requires OXYGEN as a reactant. In prokaryotes, starts in the cytoplasm and ends on the cell membrane. In eukaryotes, starts in the cytoplasm and ends in the mitochondria.

Aerobic Respiration in Eukaryotic cells First = Glycolysis = break down of glucose in the cytoplasm

Aerobic Respiration in Eukaryotic cells Second = The Krebs Cycle (Citric Acid Cycle) = occurs within the matrix of the mitochondrion = continues to break down what remains of glucose.

Aerobic Respiration in Eukaryotic cells Third = The Electron Transport Chain = Moves hydrogen ions across the cristae of the mitochondrion to produce the bulk of the ATP that is yielded by aerobic respiration.

3. Animal Structures and Processes Associated with Aerobic Respiration Structures for Gas Exchange: *Cell membrane of unicellular organisms *Outer cell layer – ectoderm, skin *Vertebrates = gills, lungs

3. Animal Structures and Processes Associated with Aerobic Respiration *Diffusion moves oxygen in and carbon dioxide molecules into and out of the cells and other structures (skin, gills, lungs) *The circulatory system aided the movement of gases.

b. Food must be obtained: *Autotrophs Photosynthesize to produce food in the cells that contain Chloroplasts. The food is then delivered to other cells by the phloem.

b. Food must be obtained: *Heterotrophs must consume food, then digest the food before it can be used for respiration.

Aerobic Respiration Equation:

*Occurs in the Cytoplasm *The Splitting of Glucose Cellular Respiration *Occurs in the Cytoplasm Starts With GLYCOLYSIS *The Splitting of Glucose

NAD picks up Hydrogen = NADH Produces 2 ATP Produces 2 molecules of Releases Hydrogen NAD picks up Hydrogen = NADH Produces 2 ATP Produces 2 molecules of Pyruvic Acids *More ATP can be produced by breaking down the pyruvic acids. *Moves to the Aerobic Pathway

*In the matrix of the Mitochondria Pyruvate *A series of chemical reactions that breaks down pyruvate to make more ATP Goes to The Krebs Cycle *In the matrix of the Mitochondria

NAD and FAD pick up H = NADH and FADH2 The Krebs Cycle Produces Carbon Dioxide -Diffuses out of the cell as waste. Produces 2 ATP NAD and FAD pick up H = NADH and FADH2

Electron Transport Chain Across the cristae of the mitochondria. Hydrogen ions from Krebs Cycle *A series of enzymes that move the hydrogen ions across the cristae to create more ATP Enters the Electron Transport Chain Across the cristae of the mitochondria.

In the Final Step, Hydrogen is combined with Oxygen to create water Produces 32-34 ATP *This process removes hydrogen from the system to allow more hydrogen to move through the chain.

ATP and Aerobic Respiration Bozeman Biology Respiration Crash Course Video ATP and Aerobic Respiration Bozeman Biology Respiration

Fermentation Does NOT use oxygen Occurs only in the Cytoplasm = Consists only of GLYCOLYSIS = only 2 ATP of energy produced. Results in a variety of waste products (based on the type of fermentation and organism involved)

Type of Fermentation = Lactate Fermentation Example 1 = Lactobacillus sp. bacteria GLYCOLYSIS * In the Cytoplasm Produces 2 ATP Pyruvate is converted to Lactate (Lactic acid) = waste

Example #1 = Importance to Humans * Lactobacillus sp. bacteria are used in the production of some dairy products. The bacteria feed on milk sugars, producing lactic acid which decreases the pH of the milk and causes the milk to thicken. This enhances the flavor/texture of the food. Examples = yogurt, cheeses, sour cream, buttermilk

Example #2 = Importance to Humans Lactobacillus bacteria feed on the sugars in cucumbers and cabbage which produces lactic acid and “sours” (changes the pH and texture) the vegetables = pickles and sauerkraut.

Example #3 = Importance to Humans Some Lactobacillus bacteria can be found living in the human mouth. They feed on the sugars left behind after a meal and produce lactate which can destroy tooth enamel = cavities.

Example 4= Lactic acid production in human muscle cells . REMEMBER: Human muscle cells respire aerobically !!! *Muscle cell working *Not enough oxygen supplied to serve as the final H acceptor in the electron Transport Chain = ETC STOPS! = 32-34 NOT produced!!

* Krebs Cycle stop = 2 more ATP are not produced *Only Glycolysis to produce ATP (2) *Pyruvate is converted to Lactic Acid. *Result is a burning sensation (due to the lactic acid) in the muscle cells just before the cells run out of energy and stop functioning.

B. Ethanol Fermentation Example = Yeast, a unicellular fungus GLYCOLYSIS * In the Cytoplasm Pyruvate is converted to Ethanol (ethyl alcohol) = waste Carbon Dioxide is released = waste Produces 2 ATP

Example #1 – Importance to humans Yeast is used in the production of bread. * Yeast feeds on the carbohydrates in bread dough and respire. * The carbon dioxide causes the dough to rise = fluffy, porous bread after baking. *The ethanol evaporates off during baking.

Example #2= importance to humans 2.Yeast are used in the production of alcoholic beverages. * Yeast feeds on the sugars in various fruits and seeds (grapes, wheat, barley) * The ethanol produced creates the alcoholic nature of beer, wines, etc.

Example #3 = importance to humans *Soy beans and corn is fermented to produce biofuel such as Ethanol.