2. Test Date: Nov 28 th (B-DAY) Nov 29 th (A-DAY) Lab: Closed-toe shoes Thursday (BDAY) Friday (ADAY)

3. Essential Questions What is cellular Respiration? What is the equation for cellular respiration? What are the similarities/differences with photosynthesis? Stages: AerobicAnaerobic – glycolysisglycolysis – Krebs cyclefermentation – Electron Transport

4. Food A living organism such as an animal consumes food, then converts some of that food into useable ATP. The rest gets stored and converted later Proteins, carbohydrates, lipids can all be used to convert to ATP but at different rates Lipids give long term large amounts of energy carbs give short term quick energy Proteins give the least amount of useable energy, so body usually stores it instead of converting it

5. The role of ATP Adenosine Triphosphate is the energy currency in living organisms It cannot be stored-instead glucose is stored and converted as the body needs it. This conversion is called cellular respiration When ATP is made, it then can be released and used by the cells in functions such as making proteins, active transport, and maintaining homeostasis Glucose must be converted slowly in order to get the maximum amount of ATP from it. It does this in stages

6. Cellular Respiration Overview Goal: to convert chemical energy (food) into useable energy (ATP) Two types – aerobic  in the presence of oxygen – anaerobic  without oxygen Glycolysis is the first step regardless if there is oxygen or not – takes place in the cytoplasm of the cell

7. Equation

9. Glycolysis-pre step Goal: One molecule of glucose is broken in half, producing two molecules of pyruvic acid Steps: – Two ATP molecules are used to break down a glucose molecule – It is split into two three carbon molecules (3Carbon; 3C) called PGAL. Enzymes rearrange the molecules – Energized electrons from the molecules are transferred to molecules of NAD+ to make NADH – A series of reactions converts the PGAL molecules to pyruvate, which will enter the mitochondria for cellular respiration – 4ATP are made, but two were used to begin with, so only 2ATP are gained Equation: – Glucose+2ATP  2Pyruvate+NADH+4ATP

11. Oxidative Decarboxylation Pyruvic acid then comes into the mitochondrial matrix It reacts with a molecule of coenzyme A to form acetyl coenzyme A, abbreviated acetyl CoA In the process, a carbon dioxide molecule is released as waste, and a molecule of NAD+ is reduced to NADH

12. Krebs Cycle (citric acid cycle)-aerobic Named after Sir Hans Adolf Krebs Each (2) acetyl CoA will enter the Kreb’s cycle and be transformed into several products: – 4NADH – 3CO 2 – FADH 2 – 1ATP Equation: 2 Acetyl CoA  8NADH+6CO 2 +2FADH 2 +2ATP

13. Steps to Krebs Cycle 1.Acetyl CoA combines with oxaloacetic acid (4C) to produce citric acid (6C) which in turn regenerates the coenzyme A 2.Citric acid releases a CO2 molecule and a hydrogen atom to form a 5C compound. The hydrogen in transferred to NAD+ reducing it to NADH 3.The 5C molecule releases a CO2 molecule and a H atom to form a 4C compound. Again, NAD+ is reduced to NADH. Also, an ATP is synthesized from ADP 4.The 4C compound from step 3 releases a hydrogen to form another 4C compound. This time FAD is reduced to form FADH2 5.The 4C from step 4 releases an H atom to regenerate oxaloacetic acid, which keeps the Krebs cycle operating. The H atom reduces NAD+ to NADH

15. Electron Transport Chain The electron transport chain is a series of chemical reactions ending with hydrogen combining with oxygen to form water. Carbon dioxide is released as a waste product as it is formed in several stages of the Krebs cycle. The NADH and FADH2 are converted into ATP – 1 NADH=3 ATP and 1FADH2=2ATP Each reaction produces a small amount of energy, which by the end of the cycle produces 38 ATP molecules, but two are spent in glycolysis so the net gain is 36 ATP

16. O2 + C6H12O6  CO2 + H2O + 36ATP

17. Anaerobic respiration Glycolysis-same glycolysis as aerobic respiration – One glucose is split into two pyruvate producing two ATP total Fermentation-Two types, both named after products in which they produce. Aerobic respiration produces water – Lactic acid  – Alcoholic 

18. Equation

19. Lactic Acid Fermentation Lactic acid fermentation occurs when oxygen is not available, for example, in muscle tissues during rapid and vigorous exercise when muscle cells may be depleted of oxygen. The pyruvic acid formed during glycolysis is broken down to lactic acid, and in the process energy is released (which is used to form ATP). Glucose  Pyruvic acid  Lactic acid + energy The process of lactic acid fermentation replaces the process of aerobic respiration so that the cell can continue to have a continual source of energy even in the absence of oxygen, however this shift is only temporary and cells need oxygen for sustained activity. Lactic acid that builds up in the tissue causes a burning, painful sensation.

20. Alcoholic Fermentation Alcohol fermentation occurs in yeasts and some bacteria. In this process, pyruvic acid formed during glycolysis is broken down to produce alcohol and carbon dioxide, and in the process energy is released (which is used to form ATP). Glucose  Pyruvic acid  alcohol + carbon dioxide + energy

21. Why learn about fermentation? Cheese Bread Alcohol Wine

22. Venn Diagram