Warm-up Make sure your Photosynthesis Review Handout is completed

Why do we eat food? When chemical bonds in food are broken, cell obtain energy.

ATP There are many different forms of energy, but the main form of energy for living organisms and their cells is Adenosine Triphosphate or ATP.

Storing Energy in ATP What makes this molecule special is that it can store energy when it adds the third phosphate group. With only two phosphate groups, the molecule is ADP or Adenosine Diphosphate.

Why are their two kinds? What is the difference? ATP and ADP? ATP is great for storing energy, but not for long periods of time. So.... Cells have ADP molecules. They use the energy from Carbohydrates (and Fats) to add a phosphate to ADP to create ATP when needed.

ATP = stored energy

SO...How do we get the energy out of the ATP molecule? When the third phosphate is removed from ATP, the chemical bond releases the energy and the cell uses it.

ATP is the molecule cells actually use for ENERGY!! How do we make ATP?

Cellular Respiration Cells go through a process (chemical reaction) of Cellular Respiration to breakdown Glucose (Sugar) and produce ATP molecules. Cellular Respiration- Glucose = ATP ALL CELLS (ALL LIVING ORGNISMS) go through some form of cellular respiration, so they can get the energy they need.

Cellular Respiration is Divided into TWO steps: 1)Glycolysis 2) Aerobic Respiration or Anaerobic Respiration

Glycolysis 1. Starts in the Cytoplasm 2. Through a series of reactions, One molecule of glucose is converted to 4 ATP molecules and 2 molecules of Purvic Acid ATP molecules are used up to get things going and the remain 2 ATP molecules are ready to be used by the cell. 4. The Purvic Acid is used in the next step> Glucose → 2 ATP + 2 Purvic Acids

NEXT There are TWO possibilities depending on whether or not oxygen is present.

Aerobic Respiration Must have oxygen to occur Takes place in the Mitochondrion Produces a NET gain of 36 ATP molecules (including the two ATP made during Glycolysis) Divided into two stages: Krebs Cycle and Electron Transport Chain

Krebs Cycle 5. Take the Purvic acid made in Glycolysis is converted into 2 ATP molecules and Carbon Dioxide 6. The Carbon Dioxide is released and the ATP available to be used by the cell. the reaction continues into the next step>

Electron Transport Chain 7. Oxygen is used in this stage to make water and 32 ATP molecules. 8. Water is used or release and the ATP is available to be used by the cell.

In summary: Aerobic Respiration In Words: Glucose + Oxygen → Carbon Dioxide + Water + 36 ATP In Chemical Formula: C 6 H 12 O 6 + 6O 2 → 6CO 2 + 6H 2 O + 36 ATP

How do your cells get energy when you use up oxygen so quickly that you cannot get more fast enough? And what about organisms that live in places where there isn't oxygen? How do their cells get energy from food?

Anaerobic Respiration (Fermentation) NO Oxygen is needed Takes place in the cytoplasm It allows glycolysis to happen over and over again. Therefore, from one glucose molecule produces 2 ATP molecules

There are TWO examples of Anerobic Respiration

Grab Your Composition Notebook and Get out Your Data Sheet from Friday

1. Lactic Acid Fermentation Performed in Animal Cells and Bacteria Cells Converts Glucose into Lactic Acid and Energy Glucose → Lactic Acid + 2 ATP

2. Alcoholic Fementation Performed by plant and yeast cells Converts glucose into Alcohol, Carbon Dioxide, and Energy Glucose → Alcohol + Carbon Dioxide + 2 ATP

Lab: Detailed Procedures Weigh Carrots Measure100 ml of water using a graduated cylinder Add water to cups Label each cup Tie up carrots with yarn Set all carrots in each beaker