5/6/13 Living Environment

1. 5/6/13 Living Environment Attendance Tests: Shantese, Jamila, Lakota I have storybooks from: Heather, Julisa, Mawazo, Destiny, Calisa, Shantese I have Finch labs from:Shantese,Trev, Iesha, Jamila, Samiyah, Naima, Calisa, Lakota, Julisa, Mawazo, Destiny

2. Genetic Engineering • Genetic Engineers can alter the DNA code of living organisms. • Selective Breeding • Recombinant DNA • PCR • Gel Electrophoresis • Transgenic Organisms

3. Selective Breeding • Breed only those plants or animals with desirable traits • People have been using selective breeding for 1000’s of years with farm crops and domesticated animals.

4. Recombinant DNA • The ability to combine the DNA of one organism with the DNA of another organism. • Recombinant DNA technology was first used in the 1970’s with bacteria.

5. Recombinant Bacteria • Remove bacterial DNA (plasmid). • Cut the Bacterial DNA with “restriction enzymes”. • Cut the DNA from another organism with “restriction enzymes”. • Combine the cut pieces of DNA together with another enzyme and insert them into bacteria. • Reproduce the recombinant bacteria. • The foreign genes will be expressed in the bacteria.

6. Benefits of Recombinant Bacteria • Bacteria can make human insulin or human growth hormone. • Bacteria can be engineered to “eat” oil spills.

7. The DNA of plants and animals can also be altered. PLANTS • disease-resistant and insect-resistant crops 2. Hardier fruit 3. 70-75% of food in supermarket is genetically modified.

8. How to Create a Genetically Modified Plant 1.Create recombinant bacteria with desired gene. 2. Allow the bacteria to “infect" the plant cells. 3. Desired gene is inserted into plant chromosomes.

9. What do you think about eating genetically modified foods?

10. Genetically modified organisms are called transgenic organisms. TRANSGENIC ANIMALS • Mice – used to study human immune system • Chickens – more resistant to infections • Cows – increase milk supply and leaner meat 4. Goats, sheep and pigs – produce human proteins in their milk

11. Transgenic Goat . This goat contains a human gene that codes for a blood clotting agent. The blood clotting agent can be harvested in the goat’s milk. Human DNA in a Goat Cell

12. How to Create a Transgenic Animal Desired DNA is added to an egg cell.

13. Ha Ha Ha!

14. Genetic Engineering and Crime Scenes……

15. Gel Electrophoresis • This technology allows scientists to identify someone’s DNA!

16. Steps Involved in Gel Electrophoresis 1. “Cut” DNA sample with restriction enzymes. 2. Run the DNA fragments through a gel. 3. Bands will form in the gel. 4. Everyone’s DNA bands are unique and can be used to identify a person. 5. DNA bands are like “genetic fingerprints”.

17. This powerpoint was kindly donated to www.worldofteaching.com http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.

18. EVOLUTION Chapter 15

19. Charles Darwin

20. Question for Thought • Earth has millions of other kinds of organisms of every imaginable shape, size, and habitat. This variety of living things is called biological diversity. How did all these different organisms arise? • How are they related?

21. In your own words, describe what YOU think the theory of evolution means…

22. Darwin’s Theory of Evolution • Evolution, or change over time, is the process by which modern organisms have descended from ancient organisms. • A scientific theory is a well-supported testable explanation of phenomena that have occurred in the natural world.

23. How do you think Darwin came up with his theory?

24. Voyage of the Beagle

25. Voyage of Beagle • Dates: February 12th, 1831 • Captain: Charles Darwin • Ship: H.M.S. Beagle • Destination: Voyage around the world. • Findings: evidence to propose a revolutionary hypothesis about how life changes over time

27. Darwin visited Argentina and Australia which had similar grassland ecosystems. those grasslands were inhabited by very different animals. neither Argentina nor Australia was home to the sorts of animals that lived in European grasslands. Patterns of Diversity

28. Darwin posed challenging questions. Why were there no rabbits in Australia, despite the presence of habitats that seemed perfect for them? Why were there no kangaroos in England? Patterns of Diversity

29. Living Organisms and Fossils • Darwin collected the preserved remains of ancient organisms, called fossils. • Some of those fossils resembled organisms that were still alive today.

30. Living Organisms and Fossils • Others looked completely unlike any creature he had ever seen. • As Darwin studied fossils, new questions arose. • Why had so many of these species disappeared? • How were they related to living species?

31. Fossils

32. The smallest, lowest islands were hot, dry, and nearly barren-Hood Island-sparse vegetation The higher islands had greater rainfall and a different assortment of plants and animals-Isabela- Island had rich vegetation. The Galapagos Island

33. Darwin was fascinated in particular by the land tortoises and marine iguanas in the Galápagos. Giant tortoises varied in predictable ways from one island to another. The shape of a tortoise's shell could be used to identify which island a particular tortoise inhabited. The Galapagos Island

35. Animals found in the Galapagos • Land Tortoises • Darwin Finches • Blue-Footed Booby • Marine Iguanas

36. Animals

37. The Journey Home • Darwin Observed that characteristics of many plants and animals vary greatly among the islands • Hypothesis: Separate species may have arose from an original ancestor

38. James Hutton: 1795 Theory of Geological change Forces change earth’s surface shape Changes are slow Earth much older than thousands of years Ideas that shaped Darwin’s Thinking

39. Charles Lyell Book: Principles of Geography Geographical features can be built up or torn down Darwin thought if earth changed over time, what about life? Ideas that Shaped Darwin’s Thinking

40. Lamarck

41. Tendency toward Perfection(Giraffe necks) Use and Disuse (bird’s using forearms) Inheritance of Acquired Traits Are you still paying Attention? Lamarck’s Theory of Evolution

44. Population Growth • Thomas Malthus-19th century English economist • If population grew (more Babies born than die) • Insufficient living space • Food runs out • Darwin applied this theory to animals

45. Publication of Orgin of Species • Russel Wallace wrote an essay summarizing evolutionary change from his field work in Malaysia • Gave Darwin the drive to publish his findings

46. Natural Selection & Artificial Selection • Natural variation--differences among individuals of a species • Artificial selection- nature provides the variation among different organisms, and humans select those variations they find useful.

47. Evolution by Natural Selection • The Struggle for Existence-members of each species have to compete for food, shelter, other life necessities • Survival of the Fittest-Some individuals better suited for the environment

48. Struggle For Existence & Survival of The Fittest

49. Natural Selection • Over time, natural selection results in changes in inherited characteristics of a population. These changes increase a species fitness in its environment

50. Descent • Descent with Modification-Each living organism has descended, with changes from other species over time • Common Descent- were derived from common ancestors