Part II Chapter 1 Acc Biology Notes

1. Part II Chapter 1 Acc Biology Notes

2. II. Unifying Themes of Biology 1. The Unity of life’s diversity: - Organization & Cell Theory -The Genetic Code (DNA) & Classification 2. Evolution: - Charles Darwin, Natural Selection, - Adaptations 3. Interdependence: - Relationships between living things - The Environment & Ecology

3. Themes of Biology 1. Diversity and unity of life there are millions of species of organisms Diversity = Differences

4. But how is all of life unified? • All life is organized: • Made of cells • All life has DNA: • The genetic code **all life has hereditary information inDNA • Its is found in the cell’s nucleus • It is identical in all cells of an organism

5. Cells Cells represent Unity because they are features that all organisms have in common.

6. DNA- all cells have DNA DNA is a large molecule that stores hereditary information -–DNA molecules ARE Deoxyribonucleic acid -Double helix- shape is formed by nitrogenous base pairs attached to a sugar-phosphate backbone. • It’s twisted ladder shape (double helix) is about 3 feet long in a single cell

7. “Unity of Life’s Diversity” • Taxonomy: the classification of organisms • Tree of Life: shows that all living things have descended with modification from a single common ancestor

8. Phylogenic Tree • Shows relationships: • between 3 Domains & 6 Kingdoms

9. Taxonomic Classification: • 3 domains:Bacteria, Archaea, and Eukarya. • 6 Kingdoms:Archaea, Bacteria, Protista, Fungi, Plantae, and Animalia. • Further divided into smaller Taxonomic groups: • phyla • class • order • family • genus • species

10. 3 Domains • Archaea -Prokaryotic cells (unicellular) -little understood, recently discovered life -probably oldest cells & found in extreme environments KINGDOM– Archaea • Bacteria= Prokaryotic cells (unicellular) -all the common bacteria, both good & bad -KINGDOM—Bacteria 3. Eukarya = Eukaryotic cells (have a nucleus) There are four kingdoms in Eukarya * Protista * Fungi * Plantae * Animalia

11. The Tree of Life: -The relationships by ancestry among organisms Three domains -2 are prokaryotic -1 Eukaryotic

12. 6 Kingdoms- examples Archaea, Bacteria, Protista, Fungi, Plantae, Animalia. www.ucmp.berkeley.edu www.dph.state.ct.us www.microscopy-uk.org.uk www.wetwebmedia.com usuarios.lycos.es usmo4.discoverlife.org danny.oz.au

13. (2nd Theme in Biology) 2. Evolution • Theory that organismschange over time, the driving force is the environment. • Natural Selection-process by which adaptation is passed on to the next generation for best survival. • Adaptations- -are favorable traits -Ex.- cactus plants adapted to desert

14. Science & Religion-in answer to your questions: • Occasionally, the media may report on the “conflict” between religion & science- implying that one must “choose” – or that science has “replaced” religion. • For most there is no conflict! Many famous scientists were Christians who used their Judeo-Christian belief in a rational God as the foundation for their study. • Even Evolution is NOT contrary to personal faith.

15. Charles Darwin- • English naturalist who presented compelling evidence that all species of life have evolved over time from common ancestors, through the process he called natural selection. http://oreh.pef.uni-lj.si/~markor/Darwin/Charles_Darwin.jpg

16. Darwin’s trip around the world on the H.M.S.Beagle, especially the stops in South America & the Galapagos Islands were the basis for his work.

17. Darwin saw unusual things on his voyage & tried to explain them: • Strange Fossils • Large tortoises • Many kinds of beaks on finches http://www.thisviewoflife.org/evolution/finch.jpg www.break-fresh-ground.com

18. Summary: 4 Main Parts of Darwin’s Reasoning • 1. Overproduction- more offspring are produced than can survive • 2. Genetic Variation- within a population, individuals have different traits • 3. Struggle to Survive- individuals must compete with each other to exist. • 4. Differential Reproduction- Organisms with the best adaptations to environment more likely to survive & reproduce.

19. Chapter 15 4 Main Parts of Darwin’s Reasoning Natural Selection

20. A simple example of Natural Selection • tiny fish may be able to hide under rocks and not get eaten by a predator • next generation has fewer large fish, “nature” has selected for smaller fish in that pond

21. adaptation the ability of a species to survive in a particular ecological niche, esp. because of alterations of form or behavior brought about through natural selection 21

22. According to the theory of evolution by natural selection organisms with favorable traits are better able to survive and reproduce successfully than organisms that lack these traits. Example: (Darwin’s Finches)

23. Evolution: Darwin’s Finches

24. Evolution discuss the ideas that make up the mechanism for evolution- NATURAL SELECTION. For example:

25. Biology Terms: Extra Info that you will need to know Terms about Structure & Function • Morphology–the structure and form of an organism • Anatomy– the branch of morphology that deals with internal structure Structure is almost always related to function. Example- Bird beaks- shape shows how it gets food

26. II. 3 Themes in Biology 3. Interdependence • Ecology- How organisms interact with both other organisms & the environment. • Biotic Factors – livingorganisms • Abiotic Factors- non-living part of the environment (water, temperature, soil type,etc) • Ecosystems-Communities of different living species (Biotic factors)& interact with each other & their non-living environment (Abiotic factors).

27. Ecology • Is the study of how organisms interact with each other and their physical environment. • Environment– everything- biotic & abiotic- surrounding an organism

28. Energy Relationships-study how organisms get, use & transfer energy • Sun- Source of almost all energy • Autotrophs- Organisms that make their own energy (food) (photosynthesis) • Heterotrophs– Organisms that obtain energy by eating other organisms

29. Food Chain & Food web in an Antarctic Ecosystem All food chains must start with a producer (autotroph)!!! What is the difference between a food chain & a food web?

30. Note numbers of organisms: Chart: many times more producers than large carnivores

31. Ecology Levels of Organization • ORGANISM-Simplest Level (1 living thing) • POPULATION-All the members of thesamespecies - that live in one place at a given time & make-up a breeding group. • COMMUNITY-Includes all the interacting populations in one area. • ECOSYSTEM- Includes all the living (biotic) & non-living (abiotic) factors in the environment. • BIOSPHERE- Thin layer of life around earth.

32. Levels of Organization

33. The future: Note that the human population level on planet Earth is now approaching 7 billion individuals. That’s more than five children born every second! http://www.westvalley.edu/sci/bio/

34. Sustainability: The ability to meet today’s needs without sacrificing the needs of future generations

35. Science & Society • Applied Science-knowledge from biological science can be used to improve human life • Bioethics–The study of what is right or wrong as it applies to biological concerns. • Biotechnology-technology based on biology, especially when used in agriculture, food science, and medicine • genetic engineering,& DNA Technology-making new forms of life by transferring genes from one organism into another- like inserting gene for enzyme Chymosin -from the stomach of calves into the DNA of both bacteria and yeasts-

36. technology application of scientific research to society's needs and problems 36

37. Biotechnology:Genetically engineered cheese –cheese is now cheaply made - with genetically modified yeast chymosin, (an enzyme which curdles milk, found in calves, who drink milk, but not in normal yeast!)

38. Genetic Medical Applications • Making medicine- until recently- medicine had to be collected from plants or made from chemicals. Now can make body substances like human blood clotting factors, insulin, vaccines & (HGH) HumanGrowthHormone with GM bacteria. • Making body parts- may be able to clone cells & make new organs so that no rejection occurs. May be able to grow new human liver in another organism like a pig. • May also be able to screen for diseases, create “designer babies”, cure cancer.

39. Gene Therapy • Example: replace or repair faulty gene for cystic fibrosis. • Insert a copy of good gene from healthy person into virus. • Infect patient’s lungs with virus, virus delivers good gene. Now patient can make the right protein to stop accumulation of mucus & can breathe normally. Imagine being this mother of child with CF, Daily you must massage & loose mucus. Any cold could overwhelm & cause death. Now imagine what gene therapy represents.

40. Examples: Featherless chicken • a controversial featherless chicken which they say is faster growing. • will not need to be plucked, saving money in processing plants. • they would not be suitable for cooler countries,but OK in hot climates • There was a rumor that KFC uses these already but it is not true. http://news.bbc.co.uk/1/hi/sci/tech/2000003.stm

41. Fishy Strawberries Flounder is a fish that can withstand icy cold temperatures. Scientists took the gene in the fish that Produces an antifreeze & inserted it into a plasmid of a bacterium The bacterium infected the strawberry & the flounder antifreeze gene entered the strawberry’s DNA The new GM strawberry cells are grown Into new plants that have strawberries which make a protein that keeps the fruit from frost damage. www.usbornequicklinks.com

42. GM foods- Golden Rice Golden Rice is part of the solution to world hunger & malnutrition. -Biofortified rice may alleviate life-threatening micronutrient deficiencies in developing countries-(decrease starvation) - Genetically modified- gene for provitamin A (β-carotene), is inserted into rice genome. www.goldenrice.org/

43. All living things have the same genetic building blocks DNA- deoxyribonucleic acid has 4 nitrogenous bases which make up the “alphabet” for the genetic code. SO- the same sequence of DNA (gene) codes for an enzyme, a protein or other molecule no matter which organism that gene is in. That is the basis for Gene technology

44. Biotechnology • There is currently much debate among scientists, politicians & environmentalist about the safety & quality of genetically modified products, especially foods. • It is very likely that you have already eaten multiple products that were produced with biotechnology and/or DNA technology

45. III. The Study of Biology A. The Scientific Method Steps: 1. Observation 2. Hypothesis 3. Prediction 4. Experiment 5. Data Analysis/ Conclusions 6. Communication/ Verification B. Evaluating Bias-at times, scientists have conflicts of interest. A scientist’s goal should be finding facts, not support of government agency agenda or the desired results of a pharmaceutical company.

46. Remember:Experiment terms • Control groupprovides a normal standard against which we compare results of the experimental group. • Experimental groupis identical to the control group except for one factor. • Variables: factors that change • Theory -a set of related hypotheses confirmed to be true many times • An advantage of the scientific method is that it is unbiased & repeatable.

47. Controlled Experiment A control group provides a normal standard against which the biologist can compare results with the experimental group An experimental group is identical to the control group except for one factor, the independent or manipulated variable. ***Other variables that may affect the outcome of the experiment should be the same in both control and experimental groups

48. Implementing the Scientific Method • The scientific method is used to solve problems • It is not an exact process No Experiment is a Failure • If negative results occur, a scientist can show that a certain hypothesis is not valid • An experiment can be successful even if it shows that a hypothesis is not consistent with observations

49. Communicating Ideas • Publishing or presenting experimental results • Four Parts of a Paper • Introduction – states problem and hypothesis to be investigated • Materials and Methods – what was used and how • Results – Findings using graphs, tables, charts • Discussion – conclusion, error sources, significance of experiment, and future needs are discussed • Paper submitted for Peer Review • Errors, conflict of interest and honesty is checked • Allows science a method to self-correct mistakes

50. IV. Tools & Techniques A. Microscopes 1. Types of Microscopes *Compound light microscope -shines light through a specimen (must have thin slice of object) -uses 2 lens to magnify image. *Electron microscope -SEM (scanning electron microscope) -TEM (transmission electron microscope) 2. The parts of the Microscope- see hand out