1. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Lesson #1: From Chemistry to Energy to Life: Chemistry and the Environment

2. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Objectives: Define the term law of conservation of matter Explain the fundamentals of environmental chemistry and apply them to real-world situations. Describe the molecular building blocks of living organisms.

3. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Define C onservation of Matter The principle that matter many be transformed for one type of substance into another s, but it cannot be created or destroyed.

4. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Central Case: Bioremediation of the Exxon Valdez Oil Spill A.The tanker Exxon Valdez struck a reef on March 24, 1989, in Alaska’s Prince William Sound and spilled 11 million gallons of crude oil. B.Thousands of workers employed by Exxon, with government agencies and volunteers, tackled the spill with conventional methods. C.Scientists used the opportunity to test a new way of cleaning up the spill by enlisting bacteria to naturally break down the oil in a process called bioremediation.

5. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Chemistry is crucial for understanding:  Examine many environmental issues, and you will likely discover chemistry playing a central role; chemistry is also central to developing solutions.  Chemistry is central to our understanding of … -How gases contribute to global climate change -How pollutants cause acid rain -The effects on health of wildlife and people -Water pollution -Wastewater treatment -Atmospheric ozone depletion -Energy issues  Explain the fundamentals of environmental chemistry and apply them to real-world situations.…

6. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Chemical building blocks Matter = all material in the universe that has mass and occupies space -Can be transformed from one type of substance into others -But it cannot be destroyed or created which is…  The law of conservation of matter -Helps us understand that the amount of matter stays constant  It is recycled in nutrient cycles and ecosystems  Explain the fundamentals of environmental chemistry and apply them to real-world situations.…

7. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Chemical building blocks Element = a fundamental type of matter, with a given set of properties -Atoms = the smallest components that maintain an element’s chemical properties -The atom’s nucleus has protons (positively charged particles) and neutrons (particles lacking electric charge) -Atomic number = the defined number of protons -Electrons = negatively charged particles surrounding the nucleus -Balances the positively charged protons

8. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The structure of an atom

9. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Chemical building blocks Isotopes = atoms with differing numbers of neutrons -Mass number = the combined number of protons and neutrons -Isotopes of an element behave differently -Some isotopes are radioactive and decay until they become non- radioactive stable isotopes -Emit high-energy radiation

10. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Radioactive decay Half-life = the amount of time it takes for one-half of the atoms to give off radiation and decay -Different radioscopes have different half-lives ranging from fractions of a second to billions of years -Uranium-235, used in commercial nuclear power, has a half-life of 700 million years Atoms may also gain or lose electrons to become ions, electrically charged atoms

11. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Molecules & Compounds Molecules = Combinations of two or more atoms -Oxygen gas = O 2 Compounds = A molecule composed of atoms of two or more different elements -Water = two hydrogen atoms bonded to one oxygen atom: H 2 0 -Carbon dioxide = one carbon atom with two oxygen atoms: CO 2

12. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Atoms are held together with bonds Covalent bond = atoms in a molecule share electrons -For example, the atoms that bond to form H 2 0 Polar covalent bonds = Atoms share electrons unequally, with one atom exerting a greater pull -The oxygen in a water molecule attracts electrons Ionic bonds = an electron is transferred from one atom to another -Are not molecules, but are salts, such as table salt, NaCl Solutions = no chemical bonding, but is a mixture of substances (i.e., blood, oil)

13. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Water: the main reason life can exist  The chemical structure of the water molecule facilitates life. Hydrogen bond = oxygen from one water molecule attracts hydrogen atoms of another  Water’s strong cohesion allows nutrients and waste to be transported  Water absorbs heat with only small changes in its temperature, which stabilizes systems  Explain the fundamentals of environmental chemistry and apply them to real-world situations.…

14. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Additional properties of water  Less dense ice floats on liquid water  Water dissolves other molecules  Explain the fundamentals of environmental chemistry and apply them to real-world situations.…

15. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Hydrogen ions determine acidity The pH scale ranges from 0 to 14 and quantifies the acidity of solutions -Acidic solutions have a pH less than 7 -Basic solutions have a pH greater than 7 -Neutral solutions have a pH of 7 A substance with pH of 6 contains 10 times as many hydrogen ions as a substance with pH of 7

16. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Organic Compounds Organic Compounds = carbon atoms joined by covalent bonds and may include other elements -Such as nitrogen, oxygen, sulfur, and phosphorus Hydrocarbons = contain only carbon and hydrogen -The simplest hydrocarbon is methane -Hydrocarbons can be a gas, liquid or solid

17. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Macromolecules Polymers = long chains of repeated molecules -The building blocks of life Macromolecules = large-size molecules  Three types of polymers are essential to life  Proteins  Nucleic acids  Carbohydrates  Lipids (are not polymers, but are also essential)  Describe the molecular building blocks of living organisms…

18. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Proteins  Describe the molecular building blocks of living organisms…  Produce tissues, provide structural support, store and others transport energy -Animals use proteins to generate skin, hair, muscles, and tendons -Some function as components of the immune system -They can serve as enzymes, molecules that promote certain chemical reactions

19. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Nucleic acids direct the production of proteins. Deoxyribonucleic acid (DNA) and Ribonucleic Acid (RNA) carry the hereditary information of organisms -Long chains of nucleotides that contain -Sugar, phosphate, and a nitrogen base Information in DNA is rewritten to RNA RNA directs amino acid assembly into proteins Genes = regions of DNA that code for proteins that perform certain functions Genome = an organism’s genes -Divided into chromosomes  Describe the molecular building blocks of living organisms…

20. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Carbohydrates and lipids  Carbohydrates = consist of atoms of carbon, hydrogen, and oxygen -Sugars = simple carbohydrates -Glucose = provides energy for cells  Complex carbohydrates build structures and store energy -Starch = a complex carbohydrate  Lipids = a chemically diverse group of compounds grouped together because they don’t dissolve in water  For energy, cell membranes, structural support, and steroids  Describe the molecular building blocks of living organisms…

21. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings We create synthetic polymers Plastics = synthetic (human-made) polymers -Best known by their brand names (Nylon, Teflon, Kevlar) -Many are derived from petroleum hydrocarbons -Valuable because they resist chemical breakdown -Problematic because they cause long-lasting waste and pollution -Wildlife and health problems, water quality issues, harmful to marine animals -We must design less-polluting alternatives and increase recycling

22. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Organization of matter in living things  Cell = the basic unit of life’s organization. Organisms use cells to compartmentalize macromolecules. Eukaryotes = multi-celled organisms containing internal structures (organelles) -Plants, animals, fungi, protists -Ribosomes synthesize proteins -Mitrochondria extract energy from sugars and fats -Nucleus houses DNA Prokaryotes = single-celled organisms lacking organelles and a nucleus  Describe the molecular building blocks of living organisms…

23. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Hierarchy of matter in organisms Matter is organized in a hierarchy of levels, from atoms through cells through organ systems

24. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Lesson #2: From Chemistry to Energy to Life: Energy Fundamentals

25. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Objectives: Define the term autotroph (primary producer) Differentiate among the types of energy and recite the basics of energy flow. Distinguish photosynthesis, respiration, and chemosynthesis, and summarize their importance to living things.

26. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Define A utotroph (Primary Producer) An organism that produces its own food from inorganic compounds and a source of energy. There are photoautotrophs (photosynthetic plants) and chemical autotrophs.

27. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Energy fundamentals Energy = that which can change the position, physical composition or temperature of matter  Potential energy = energy of position  Kinetic energy = energy of motion  Chemical energy = potential energy held in the bonds between atoms Kinetic energy is changed into potential energy to produce motion, action, and heat  Differentiate among the types of energy and recite the basics of energy…

28. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Energy is conserved...but changes in quality  First law of thermodynamics = energy can change forms, but cannot be created or destroyed  Second law of thermodynamics = the nature of energy changes from a more-ordered to a less-ordered state -Entropy = an increasing state of disorder  Differentiate among the types of energy and recite the basics of energy…

29. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The Earth’s systems are powered by…  Light energy from the sun powers most living systems.  Geothermal energy also powers Earth’s systems.  Differentiate among the types of energy and recite the basics of energy…

30. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The sun’s energy powers life The sun releases radiation from the electromagnetic spectrum -Some is visible light Solar energy drives weather and climate, and powers plant growth

31. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Photosynthesis The sun supplies energy to those organisms that are able to use it to produce their own food; they are autotrophs, or primary producers. Autotrophs (primary producers) = organisms such as green plants, algae and cyanobacteria produce their own food from the sun’s energy  Photosynthesis = the process of turning light energy from the sun into chemical energy -Carbon dioxide + water + sun’s energy is converted into sugars and high- quality energy  Distinguish photosynthesis, respiration, and chemosynthesis, and summarize their importance to living …

32. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Photosynthesis produces food Chloroplasts = organelles where photosynthesis occurs -Contain chlorophyll = a light-absorbing pigment -Light reaction = splits water by using solar energy -Calvin cycle = links carbon atoms from carbon dioxide into sugar (glucose) 6CO 2 + 6H 2 0 + the sun’s energy C 6 H 12 O 6 + 6O 2

33. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Cellular respiration releases chemical energy The chemical energy created by photosynthesis can later be used by organisms in the process of cellular respiration.  Cells use the reactivity of oxygen to convert glucose back into its original starting materials, water and carbon dioxide, and release energy to perform tasks within cells.  This extraction of energy occurs in both autotrophs and heterotrophs, or consumers (animals, fungi, microbes). C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 0 + energy  Distinguish photosynthesis, respiration, and chemosynthesis, and summarize their importance to living …

34. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Geothermal energy powers Earth’s systems Hydrothermal vents = host entire communities that thrive in high temperature and pressure  Hydrothermal vent communities utilize chemical energy instead of light energy.  Chemosynthesis = uses energy in hydrogen sulfide to produce sugar 6CO 2 + 6H 2 0 + 3H 2 S C 6 H 12 O 6 + 3H 2 SO 4  Distinguish photosynthesis, respiration, and chemosynthesis, and summarize their importance to living …

35. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Lesson #3: From Chemistry to Energy to Life: The Origin of Life

36. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Objectives: Define the term heterotroph Itemize and evaluate the major hypotheses for the origin of life on Earth. Outline our knowledge regarding early life and give supporting evidence for each major concept. TED - Astronomer Dimitar Sasselov and his colleagues search for Earth-like planets that may, someday, help us answer centuries-old questions about the origin and existence of biological life elsewhere (and on Earth). Preliminary results show that they have found 706 "candidates" -- some of which further research may prove to be planets with Earth-like geochemical characteristics.

37. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Define Heterotroph An organism that feeds on other organisms and cannot make its own food from inorganic chemicals or a source of energy.

38. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Early Earth was a very different place 4.5 billion years ago, Earth was a hostile place -Severe volcanic and tectonic activity -Intense ultraviolet energy from the sun -No oxygen existed in the atmosphere, until photosynthesis developed in microbes -No life existed

39. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Several hypotheses explain life’s origin  Primordial soup: The heterotrophic hypothesis a.This is the idea that life evolved from a primordial soup of simple inorganic chemicals—carbon dioxide, oxygen, and nitrogen—dissolved in the ocean. b.Lab experiments have provided evidence that the proposed process could work. c.However, scientists since then have modified their ideas about early atmospheric conditions, so these experiments seem less likely to represent what actually happened.  Itemize and evaluate the major hypotheses for the origin of life on Earth…

40. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Several hypotheses explain life’s origin  Seeds from space: The panspermia hypothesis a.This is the idea that bacteria from space crashed to Earth on meteorites and started life here. b.The Murchison meteorite, which fell in Australia in 1969, contained many amino acids.  Itemize and evaluate the major hypotheses for the origin of life on Earth…

41. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Several hypotheses explain life’s origin  Life from the depths: The chemoautotrophic hypothesis. a.This is the idea that early life was formed in deep- sea vents where sulfur was abundant. b.Some of the most ancient ancestors of today’s life forms likely lived in extremely hot and wet environments.  Itemize and evaluate the major hypotheses for the origin of life on Earth…  Self-replication and cell formation were crucial steps.

42. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The fossil record teaches about life’s history The earliest evidence of life on Earth comes from 3.5-billion-year-old rocks. Whether the first life arose from deep- sea vents, tidal pools, or comet craters, we know that life diversified into countless forms over Earth’s long history, leading eventually to the planet full of life that we know today. Fossils are imprints of dead organisms in stone; fossils provide information about plants and animals in different time periods.

43. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings The fossil record shows that…  The species living today are but a tiny fraction of all the species that have ever lived.  Earlier types of organisms changed, or evolved, into later ones.  The number of species existing at any one time has increased through history.  There have been several episodes of mass extinction, or simultaneous loss of great numbers of species.  Many organisms present early in history were smaller and simpler than modern organisms.  Outline our knowledge regarding early life and give supporting evidence for each major concept…

44. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Present-day organisms help decipher history  Biologists use present-day organisms and their genes to get information about evolution and to help us decipher life’s history. Archea = single-celled prokaryotes very different from bacteria The tree of life now consists of 3 prongs: bacteria, archaea, eukaryotes  Outline our knowledge regarding early life and give supporting evidence for each major concept…

45. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings TED Video Dimitar Sasselov: How we found hundreds of potential Earth-like planets (18:31) Dimitar Sasselov works on uniting the physical and life sciences in the hunt for answers to the question of how life began. "One of the central goals of the Harvard initiative is to understand the different ways that life might form, according to Dimitar Sasselov.... 'There is no reason to think that biology would be the same from planet to planet, but physics and chemistry should be the same,' Sasselov said" - Gareth Cook, Boston Globe

46. Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum PowerPoint ® Slides prepared by Jay Withgott and Heidi Marcum Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Lesson #3: From Chemistry to Energy to Life: Lab : The Ecological Footprint Exercise

47. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Objectives: Define the term bioremediation. Take Chapter 4 quiz. Review Chapter 4 Multiple Choice Questions In class exercise to help build quantitative and analytical skills in reading graphs and making sense of data.

48. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings  Define bioremediation A method of treating groundwater pollution problems that utilizes microorganisms in the ground to consume or break down pollutants.

49. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Calculating Ecological Footprints In ecological systems, a rough rule of thumb is that when energy is transferred from plants to plant-eaters or from prey to predator, the efficiency is only about 10%. Much of this inefficiency is a consequence of the second law of thermodynamics. Another way to think of this is that eating one calorie of meat from an animal is the ecological equivalent of eating ten calories of plant material. Humans are considered omnivores because we can eat both plants and animals. The choices we make about what to eat have significant ecological consequences. With this in mind, calculate the ecological energy requirements for four different diets, each which provides a total of 2,000 dietary calories per day. DietSource of calories Number of calories consumed Ecologically equivalent calories Total ecologically equivalent calories 100% plantPlant 0% animalAnimal 90% plantPlant90% × 2,000 = 1,8001,8001,800 + 2,000 = 3,800 10% animalAnimal200200 × 10 = 2,000 50% plantPlant 50% animalAnimal 0% plantPlant 100% animalAnimal

50. Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings Calculating Ecological Footprints 1) How many ecological equivalent calories would it take to support you for a year, for each of the four diets listed? 2) How does the ecological impact from a diet consisting strictly of animal products (i.e., milk, other dairy products, eggs, and meat) compare with that of a strictly vegetarian diet? How many additional ecologically equivalent calories do you consume each day by including as little as 10% of your calories from animal sources? 3) What percentages of the calories in your own diet do you think come from plant vs. animal sources? Estimate the ecological impact of your diet, relative to a strictly vegetarian one. 4) Describe some challenges of providing food for the growing human population, especially as people in many poorer nations develop a taste for American-style diet rich in animal protein and fat.