1. Unifying Characteristics of Life 1.Order— the smallest unit of life is the cell 2.Metabolism— 3.Responsiveness—perceive and react to their environment 4.Development— 5.Heredity—genes are passed from parent to offspring 6.Evolution—populations change over time as they adapt

2. Fig 1.3 2. Molecule : 4. Cell :The simplest entity that has all the properties of life 3. Organelle : Biological Organization 1.Atom:smallest unit of an element that still retains the element’s properties

3. 7. Organ System:A group of body parts that carries out a particular function in an organism 6. Organ : 5. Tissue :A group of similar cells that carries out a particular func- tion in an organism

4. 8. Organism: individual composed of many coordinated organ systems 9. Population: 10. Community:

5. 11. Ecosystem: 12. Biosphere: Those regions of the earth’s waters, crust and atmosphere in which organisms can exist.The global ecosystem

6. The cell is the simplest structure that can perform all activities required for life Cells and Their DNA There are two major types of cells 1. 2.

7. All cells use DNA as the chemical material of genes –Genes:

8. The diversity of known life includes 1.7 million species Estimates of the total diversity range from 5 million to over 30 million species The Diversity of Life

9. EUKARYOTES Universal Ancestor Bacteria Archaea: Bacteria adapted to extreme environments Protists Plants Animals Fungi PROKARYOTES The Unity and Diversity of Life

10. The three domains of life are: The Three Domains of Life 1.Bacteria 2.Archaea 3.Eukarya

11. Domain Bacteria Domain Archaea Domain Eukarya Kingdom Protista Kingdom Plantae Kingdom Fungi Kingdom Animalia Fig 1.9

12. Underlying the diversity of life is a striking unity, especially at the lower levels of structure Unity in the Diversity of Life Evolution accounts for this combination of unity and diversity

13. The history of life is a saga of a restless Earth billions of years old EVOLUTION: BIOLOGY’S UNIFYING THEME –Fossils document this history Fig 1.10

14. Life evolves Each species is one twig of a branching tree of life extending back in time Ancestral bear Fig 1.11

15. Darwin’s book developed two main points 1. Descent with modification 2. Natural selection

16. Darwin was struck by the diversity of animals on the Galápagos Islands Natural Selection He thought of origin of new species and adaptation to the environment the as closely related processes

17. Medium ground finch Cactus ground finch Small tree finch Medium tree finch Woodpecker finch Large ground finch Small ground finch Large cactus ground finch Vegetarian finch Large tree finch Mangrove finch Green warbler finch Gray warbler finch Sharp-beaked ground finch Seed-eaters Cactus-flower -eaters Bud-eater Insect-eaters Ground finches Tree finches Warbler finches Common ancestor from South American mainland Descent with modification Fig 1.13

18. Fact 1: Fact 2: Conclusion: Unequal reproductive success Darwin’s Conclusion Darwin synthesized the concept of natural selection from two observations:

19. Fig 1.14: Natural Selection

20. The Evolution of Diversity Different species have different traits. These arise from: Mutations – – heritable changes in DNA. Mutations are adaptive if they change the organism’s ability to get food, mate, etc. Evolution – Natural selection - adaptive traits tend to increase over time. It is the mechanism of evolution

21. Darwin’s publication of The Origin of Species fueled an explosion in biological research –Evolution is one of biology’s best demonstrated, most comprehensive, and longest lasting theories –Evolution is the unifying theme of biology

22. Organisms and all other things in the universe consist of matter Matter is anything that occupies space and has mass BASIC CHEMISTRY

23. Atomic number Element symbol Mass number Periodic table of the elements

24. 25 Elements are essential to life C, H, O, N: 96% of the weight of the human body Fig 2.3

25. Atom: Fig. 2.02 (a) Hydrogen atom (b) Carbon atom(c) Oxygen atom Proton NeutronElectron Atomic nucleus First shell Second shell

26. The subatomic particles of an atom Atomic Structure Proton Neutron Electron Nucleus - Consists of neutrons and protons

27. Electrons The number of electrons in the outermost shell… Chemical Properties of Atoms

28. Electron First electron shell: can hold 2 electrons Outermost electron shell: can hold 8 electrons Carbon (C) Atomic number = 6 Nitrogen (N) Atomic number = 7 Oxygen (O) Atomic number = 8 Hydrogen (H) Atomic number = 1 Fig 2.7

29. Chemical reactions: –2 types of molecular bonding: Ionic Bonds Covalent bonds Chemical Bonding and Molecules

30. When an atom loses or gains electrons, it becomes electrically charged = ion –Ionic bonds Ionic Bonds Sodium atom Chlorine atom Complete outer shells Na  Cl  Sodium chloride (NaCl) Fig 2.8

31. (a) Hydrogen atom (H) (c) Sodium atom (Na) (b) Hydrogen ion (H + ) (d) Sodium ion (Na + ) 1 electron 1 proton No electrical charge 11 electrons 11 protons No electrical charge No electron 1 proton 10 electrons 11 protons Atoms: electrically neutral Ions: Electrically charged

32. Covalent Bonds Fig 2.9

33. Covalent bonding in water Full shell with 8 electrons – Slightly negative Hydrogen atoms with unfilled shells Full shells with 2 electrons each + Slightly positive + Covalent bond (shared pair of electrons) Oxygen atom with unfilled shell Water molecule (H 2 O)

34. The polarity of water results in….. ()() Hydrogen bond ()() ()() ()() ()() ()() ()() ()() The Structure of Water Fig 2.10

35. 1. Water as the Solvent of Life Ion in solution Salt crystal Fig 2.16

36. Dissolving of Sodium Chloride, NaCl, in Water Salt Water Electrical attraction Water molecules (H 2 O) Hydrogen bonds Edge of one salt crystal Ionic bond Water molecules dissolve NaCl, breaking ionic bond

37. Cohesion = Microscopic tubes

38. What are plants made of? The Four Most Important Organic Biological Compounds 1.Carbohydrates 2.Lipids 3.Proteins 4.Nucleic Acids

39. C:H:O ratio is 1:2:1 (CH 2 0)n Simple sugars:  Structural units, used to make larger, storage compounds: 1.Starch – 2.Glycogen – 3.Cellulose – 1) Carbohydrates

40. Fig 3.13

41. Glucose Fructose Formation of a Disaccharide C 12 H 22 O 11 GlucoseFructose H 2 O (water) Sucrose A portion of a polysaccharide Monosaccharides C 6 H 12 O 6 (Simple sugars)

42. 2. Lipids Non-polar, hydrophobic (don’t dissolve in water) (CH) n COOH Functions:

43. A) Fats Triglycerides – most abundant lipids in body, abundant energy!

44. Fig. 3.15

46. B) Phospholipids

48. 3) Proteins Fig. 3.20

49. Fig 3.21

50. Proteins continued

51. Primary structure Fig 3.22

52. Fig 3.24

53. 4) Nucleic Acids DNA & RNA Monomers of Nucleotides Fig 3.26

54. Fig 3.27 The nitrogenous bases of DNA

55. RNA contains: ribose instead of deoxyribose, and uracil instead of thymine Fig 3.29

56. Fig 3.28: The structure of DNA