Cellular Respiration April 9, 2013 Mr. Alvarez
Do Now: Answer on a sheet of Loose-leaf 1) What is the equation for Photosynthesis 2) Explain how plants (leaves) regulate water loss use term negative feedback 3) Where do light-dependent reactions occur in the chloroplast? Where do the dark-reactions occur?
Cellular Respiration Respiration- Breathing Cellular Respiration- energy releasing pathway in a cell Oxygen is needed to release energy When we breathe, we respire ***Cellular Respiration takes place in the Mitochondria***
Chemical Energy and Food 1 Glucose molecule contains 3811 calories of heat energy calorie- Amount of energy needed to raise the temperature of 1 gram of water 1 degree Celsius Calorie (Capital C) on food labels is actually a kilocalorie or 1000 calories
Cellular Respiration Cellular Respiration- Process that releases energy by breaking down glucose and other food molecules in the presence of Oxygen Aerobic Respiration- Requires Oxygen Consists of 3 stages: Glycolysis Krebs Cycle Electron Transport Chain
Cellular Respiration Formula 6O 2 + C 6 H 12 O 6 6CO 2 + 6H 2 O + Energy Oxygen + Glucose Carbon Dioxide + Water + Energy
Glycolysis Glyco comes from the Greek work glukus Glukus- Sweet Sugar is sweet, glucose is a sugar Lysis- Process of breaking down Glycolysis- Breaking down Glucose
Glycolysis Glycolysis- The process in which one molecule of glucose is broken in half, producing 2 molecules of pyruvic acid, a 3 carbon compound o 2 ATP go in 4 ATP come out o 2 NAD+ go in 2 NADH come out NAD+ - nicotinamide adenine dinucleotide o Hold high energy electrons o Similar to NADP+ in Photosynthesis
Glycolysis Formula Glucose + 2 ATP + 2 NAD+ 2 Pyruvic Acid + 4 ATP + 2NADH
Krebs Cycle Krebs Cycle- Pyruvic Acid is broken down into Carbon Dioxide in a series of energy-extracting reactions Takes place in the Mitochondrial Matrix
Electron Transport Chain Electron Transport Chain- uses high-energy electrons from the Krebs Cycle to convert ADP into ATP o Occurs in the Mitochondrial Inner Membrane
Totals Aerobic Respiration- 2 molecules of ATP go in, 38 molecules of ATP come out. Creates a total of 36 ATP molecules Turns 38% of total energy from Glucose into usable energy The remaining 62% of energy gets released as heat
Anaerobic Respiration Mr. Alvarez April 11, 2013
Anaerobic Respiration Anaerobic Respiration- Reactions that do not require Oxygen Fermentation- Releases energy from molecules by producing ATP in the absence of Oxygen o There are 2 types of Fermentation o Alcoholic Fermentation o Lactic Acid Fermentation
Alcoholic Fermentation Occurs after Glycolysis if no oxygen is present Pyruvic Acid + NADH Alcohol + CO 2 + NAD + Produces alcoholic beverages Yeast use this process to make bread dough rise
Lactic Acid Fermentation Also can occur after Glycolysis if no oxygen is present Pyruvic Acid + NADH Lactic Acid + NAD+ Lactic Acid is produced in muscles during rapid exercise Build up of Lactic Acid in muscle causes painful burning sensation This is the reason why muscles feel sore.
Aerobic vs. Anaerobic Respiration Aerobic produces 36 molecules of ATP Anaerobic Produces 2 molecules of ATP
Energy and Exercise When a sprinter pushes off the starting blocks, he is using 3 pathways to obtain energy Sprinter is using: ATP already in the muscles ATP made by lactic acid fermentation Cellular Respiration (Aerobic)
Quick Energy Muscle cells contain small amounts of stored ATP Depleted within seconds Lactic Acid Fermentation can supply ATP to last about 90 seconds Produces Lactic Acid as a byproduct Only way to get rid of Lactic Acid is by chemical reactions that require Oxygen This is why heavy breathing occurs after heavy exercise
Long Term Energy Cellular Respiration is the only way to generate a continuous supply of ATP It releases energy more slowly than Fermentation so athletes must pace themselves Body stores energy in muscles and other tissues in the form of glycogen Glycogen usually lasts for about 15-20 minutes of activity After Glycogen is depleted, the body starts to break down fats.
Comparing Photosynthesis & Cellular Respiration Photosynthesis and Cellular Respiration are opposites Photosynthesis stores energy while Cellular Respiration uses energy Photosynthesis removes Carbon Dioxide from the atmosphere while Cellular Respiration puts Carbon Dioxide back into the atmosphere Photosynthesis releases Oxygen while Cellular Respiration uses that Oxygen to release energy
Comparing Photosynthesis & Cellular Respiration Photosynthesis Cellular Respiration Function Energy Capture Energy Release Location Chloroplasts Mitochondria Reactants (What goes in) Products (What comes out) CO 2 and H 2 O C 6 H 12 O 6 and O 2 C 6 H 12 O 6 and O 2 CO 2 and H 2 O Equation 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2 C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O Energy Captured (In) Released (Out)
HOMEWORK In the Review Book: Read Pages 20-25 Answer questions 1-22 You MUST answer 8, 17, 19