Unit 5 – Cellular Energy

1. Unit 5 – Cellular Energy The orange sections summarize key information and vocabulary terms are underlined. Image

2. What is energy? • All life depends on energy, or the ability to do work, in order to function. • The original source of all energy on Earth is the sun. • All cellsareconstantly using energy. • Energy is stored in the chemical bonds of compounds such as carbohydrates and lipids. http://www.noaanews.noaa.gov/stories2005/images/sun-soho011905-1919z.jpg

3. Photosynthesis Textbook Reference pg. 225 • Photosynthesis is the process by which autotrophs (photosynthetic organisms) convert the energy of sunlight into glucose. http://static.howstuffworks.com/gif/irrigation-photosynthesis.gif

4. Photosynthesis Cont. • Photosynthesis creates glucose using carbon dioxide, water, and energy from the sun. • The chemical equation for photosynthesis: 6CO2 + 6H2O + Sunlight a C6H12O6 + 6O2 (Carbon Dioxide) (Water) (Energy) (Glucose) (Oxygen) http://www.ap.stmarys.ca/~ishort/Images/Earth/Atmos/photosynthesis.jpg

5. Photosynthesis Cont. • Chloroplasts are the organelles in where photosynthesis occurs. • Chlorophyll is the main pigment that absorbs light energy from the sun within the chloroplasts. http://botit.botany.wisc.edu/images/130/Ferns/Gametophyte_Images/Chloroplasts_MC.low.jpg

6. Thylakoid vs Stroma • Sketch a simplified diagram of a chloroplast in your notebooks, include the following labels: • Thylakoid • Stroma • Image

7. Photosynthesis Stage 1 • Textbook Reference pg. 226-228 • Light Dependent Reaction: • (Requires water and sunlight) • Takes place in a part of the chloroplast called the thylakoid, a sac-like membrane within the chloroplast where chlorophyllabsorbs the light energy • Lightenergy transferred to electronsin the electron transport chain • Move to the stroma; uses NADP+ and 2 electrons to make NADPH • Onewatermolecule is split to produce ATP and release oxygen from the chloroplast

8. Knowledge check • Turn and talk to your table mates: • Where does light go in the thylakoid? • What happens to water? • Image

9. Photosynthesis Stage 2 • Textbook Reference pg. 228-230 • Light Independent Reaction: • Calvin Cycle (Without light) • Takes place in the stroma(gel like material outside thethylakoidmembranes in the chloroplast) • Series of reactions that use CO2 + ATP to make glucose to use for energy • Video http://www.chimicare.org/curiosita/wp-content/uploads/2011/11/schema-semplificato-fotosintesi-in-un-cloroplasto.gif

10. Cellular RespirationTextbook Reference pg. 231 • Cellular respiration occurs in the mitochondria of ALL eukaryotes, while photosynthesis occurs only in plants and other photosynthetic life. • Itreleases energy by breaking down glucose and other food molecules, most often in the presence of oxygen. • The chemical equation for cellular respiration: C6H12O6+ 6O2 a 6H2O + 6CO2 + ATP (Glucose) (Oxygen) (Water) (Carbon Dioxide) (Energy) http://en.wikipedia.org/wiki/File:Auto-and_heterotrophs.png

11. Matrix vsIntermembrane Space • Sketch a simplified diagram of a mitochondrion in your notebooks, include the following labels: • Cristae • Matrix • (L) Image ; (R) Image

12. Cellular Respiration stage 1 Textbook Reference pg. 231-232 • Glycolysis: • Takes place in the cytoplasm • Reaction converts glucose (using ATP) in to 2 molecules of pyruvic acid [C3H4O3]. • Pyruvic acid then moves through the mitochondrial membrane, converts to acetyl-CoA and gives off CO2. Biology – The Dynamics of Life, pg. 232

13. Knowledge Check Biology – The Dynamics of Life, pg. 232 • Turn and talk to your table mates: • What products are formed as a result of the reactions within the mitochondrion?

14. Cellular Respiration stage 2 Textbook Reference pg. 231-232 • Citric Acid Cycle [AKA Kreb’s Cycle]: • Takes place in the matrix of the mitochondrion • Complicated reactions convert acetyl-CoA to ATP and CO2 • Uses multiple enzymes and ATP to carry out the process • Uses NAD+ and FAD as electron carriers to create NADH and FADH2

15. Knowledge check • Turn and talk to your table mates: • How many different conversions does Acetyl CoA go through? • What products are formed as a result of these reactions? • Image

16. Cellular Respiration stage 3 Textbook Reference pg. 234 • Electron Transport Chain: • Takes place in the folds of the cristaeof the mitochondrion • Complicated reactions move NADH and FADH2 through transport proteins within the membrane to create ATP and H2O • End result = 36 ATP molecules for every glucose http://www.teachersdomain.org/assets/wgbh/tdc02/tdc02_img_electronchai/tdc02_img_electronchai.jpg

17. ATP = Energy Textbook Reference pg. 222-224 • The ATP created during cellular respiration is one of the most important compounds within cells because it is used to store/release energy. Adenosine Tri Phosphate(AKA ATP) • Think of ATP as a fully charged battery, ready to do work for the cell. • When the bonds in the compound are broken in ATP, energy is released. http://www.ustboniface.mb.ca/cusb/abernier/Biologie/Module1/Images/atp.jpg

18. ATP Cont. • Observe the simulation; breakingoff the last phosphate creates ADP (Adenosine Di Phosphate)and releases energy to be used in the cell. http://student.ccbcmd.edu/biotutorials/energy/images/atp.gif

19. Respiration without oxygen = Fermentation Textbook Reference pg. 235-236 • There are times when mitochondria within your cells cannot get enough O2to support the cells’ energy needs. • Anaerobic respiration is respiration to create ATP in the absence of oxygen, known as fermentation. • Fermentation producesmany items found in the home • Types of Fermentation: • Lactic acid fermentation • Alcoholic fermentation O2 http://visionhelp.files.wordpress.com/2012/01/no-symbol.jpeg

20. Lactic Acid vs Alcoholic Fermentation • Lactic Acid Fermentation • Fermentation that mainly occurs in the muscle cells of animals and a few other types of cells • Lactic acid is produced during this form of respiration; it is filtered out in the liver of animals • Causes muscles to be sore after a hard workout • Dairy industry uses LAF in bacteria tomake cheese • Other microbe fermentation creates soy sauce from soy beans • End result = 2 ATP molecules for every glucose

21. Lactic Acid vs Alcoholic Cont. • Alcoholic Fermentation • Fermentation that mainly occurs in yeast and a few types of bacteria • Ethanol [a type of alcohol] is produced during this form of respiration; it is toxic waste released by the yeast in to their surroundings • Wine industry uses AF tomake wine; yeasts die in the wine vat when the alcohol concentration reaches 14% • End result = 2 ATP molecules for every glucose • Video

22. http://academic.pgcc.edu/~kroberts/Lecture/Chapter%205/05-23_ProductsOfFerment_L.jpghttp://academic.pgcc.edu/~kroberts/Lecture/Chapter%205/05-23_ProductsOfFerment_L.jpg

23. Endosymbiotic Theory Textbook Reference pg. 384-385 • Fossil record indicates that eukaryotes first appeared ~2 billion+ years ago – how did these cells containing complex organelles, evolve? • Endosymbiotic Theory, first proposed by Lynn Margulisof the University of Massachusetts, suggests that chloroplasts and mitochondria [w/ their own DNA & ribosomes] – historically, were prokaryotic organisms that lived within [“living together”] other, larger cells, slowly evolving over time. Dr. Lynn Petra Margulis, Evolutionary Biologist, 1938-2011 Image

24. Endosymbiotic Theory Cont. http://dontdontoperate.files.wordpress.com/2011/03/endosymb.gif

25. Photosynthesis without chloroplasts? • Cyanobacteria are photosynthetic prokaryotes – but how do they photosynthesize without chloroplasts? • oldest known fossils, 3.5+ billion years old • contain chlorophyll and have thylakoid-like plasma membranes with multiple layers for photosynthesis http://photosynthesis.sbcs.qmul.ac.uk/mullineaux/CellBiol.html

26. Respiration without mitochonria? • Prokaryotes need ATP to fuel cell processes – but how do they create ATP without mitochondria? • process occurs in specialized membranes and the cytoplasm http://textbookofbacteriology.net/themicrobialworld/Structure.html