III. Cells and Energy

A. Energy Transfer in Cells 1.Carbohydrates such as glucose provide energy for the cell. However, they cannot be used directly, They must be converted to ATP 2.ATP Adenosine Triphosphate is the energy molecule of the cell.

Adenosine Triphosphate

3. How ATP works ATP links Anabolism (building molecules) and catabolism (breaking down molecules)!!!!! Catabolism ATP is formed from ADP and P i when energy is released by breaking the bonds of fuel molecules during cellular respiration Anabolism When ATP is broken down forming ADP and P i energy is released to build molecules such as proteins

4. How ATP is Produced: Respiration INOut Glucose Oxygen ADP Free Phosphate(P i ) Carbon Dioxide Water Mitochondrion The ATP can be used directly to power life processes ATP

B. Capturing Light Energy: Photosynthesis 1. Requirements and products of photosynthesis IN Out Carbon Dioxide Water Light Energy Glucose Oxygen Water Chloroplast

2. Stages of Photosynthesis A) Light Reaction - traps light energy to make ATP –Light strikes chlorophyll and electrons are boosted to a high energy state –Electrons flow down the electron transport chain and convert ADP to ATPelectron transport chain B) Water is split –NADP captures hydrogen and becomes NADPH –Oxygen is given off as waste C) The ATP and NADPH are used in the Dark reaction

A photon of light strikes chlorophyll and a water molecule is split As electrons move down the electron transport chain, hydrogen ions are pumped into thylkoid Light boost the electron to a NADP forming NADPH Hydrogen ions flow through ATPsyntase forming ATP from ADP ATPsyntaseATP

3. 2 nd Stage of Photosynthesis: Dark Reaction - Uses the ATP from the light reaction to join the carbon dioxide (from the atmosphere) and hydrogen (from NADPH) to form glucose in a series of reactions called the Calvin Cycle IN Out Calvin Cycle Carbon Dioxide NADPH ATP Glucose NADP ADP + P i

The Calvin Cycle Carbon dioxide joins with RuBP to form a six carbon molecule The six carbon molecule splits forming 3 carbon molecule called 3-PGA Energy from ATP and hydrogen from NADPH are added forming G3P One molecule of 3GP exits The remaining molecule are converted to RuBP

C. Energy Release 1. Anaerobic Respiration- the breakdown of glucose to produce 2ATP without using oxygen. a) Glycolysis- breaking glucose in two. This produces 2 ATP and Lactic acid 1) Lactic acid causes muscle fatigue 2) Lactic Acid produced by bacteria gives food a sour taste. Vinegar, sour cream, pickles etc Bacteria INOUT Glucose 2(ADP + P i) Lactic Acid 2 ATP

Anaerobic Respiration b) Fermentation - breaking down glucose into Alcohol and Carbon Dioxide to produce 2 ATP 1)Fermentation produces beer and wine 2)Fermentation causes bread to rise Yeast INOut Glucose Alcohol Carbon Dioxide 2ATP 2(ADP + P i)

Aerobic Respiration 2. Aerobic Respiration- The break down of glucose with oxygen to produce 38 ATP. Involve 4 Steps: Step 1: Glycolysis (Occurs in cytoplasm)Glycolysis Glucose is broken in half producing Pyruvic Acid and 2 ATP

Step 2: Pyruvic Acid Conversion (in Mitochondria) Pyruvic acid is converted to Carbon Dioxide and Acetyl groups Carbon Dioxide Acetyl Groups Pyruvic Acid

Step 3: Kreb’s CycleKreb’s Cycle The Acetyl groups have their hydrogen stripped away releasing CO 2 and 2 ATP Acetyl groups Hydrogen NAD  NADH Carbon Dioxide 2 ATP Kreb’s Cycle

Step 4: Electron Transport ChainElectron Transport Chain Hydrogen moves down the electron transport chain producing 34 ATP. The hydrogen then joins with oxygen to form water ADP + P i 34 ATP