Table of contents
- 1. Introduction to Biology(61)
- 2. Chemistry(39)
- 3. Water(33)
- 4. Biomolecules(81)
- 5. Cell Components(60)
- 6. The Membrane(46)
- 7. Energy and Metabolism(55)
- 8. Respiration(54)
- 9. Photosynthesis(59)
- 10. Cell Signaling(24)
- 11. Cell Division(54)
- 12. Meiosis(55)
- 13. Mendelian Genetics(93)
- Introduction to Mendel's Experiments(3)
- Genotype vs. Phenotype(6)
- Punnett Squares(4)
- Mendel's Experiments(5)
- Mendel's Laws(5)
- Monohybrid Crosses(5)
- Test Crosses(7)
- Dihybrid Crosses(5)
- Punnett Square Probability(10)
- Incomplete Dominance vs. Codominance(5)
- Epistasis(2)
- Non-Mendelian Genetics(8)
- Pedigrees(4)
- Autosomal Inheritance(7)
- Sex-Linked Inheritance(13)
- X-Inactivation(4)
- 14. DNA Synthesis(54)
- 15. Gene Expression(74)
- Central Dogma(6)
- Introduction to Transcription(4)
- Steps of Transcription(8)
- Eukaryotic RNA Processing and Splicing(7)
- Introduction to Types of RNA(6)
- Genetic Code(12)
- Introduction to Translation(4)
- Steps of Translation(5)
- Post-Translational Modification(5)
- Review of Transcription vs. Translation(4)
- Mutations(13)
- 16. Regulation of Expression(57)
- Introduction to Regulation of Gene Expression(2)
- Prokaryotic Gene Regulation via Operons(9)
- The Lac Operon(7)
- Glucose's Impact on Lac Operon(5)
- The Trp Operon(5)
- Review of the Lac Operon & Trp Operon(2)
- Introduction to Eukaryotic Gene Regulation(5)
- Eukaryotic Chromatin Modifications(5)
- Eukaryotic Transcriptional Control(8)
- Eukaryotic Post-Transcriptional Regulation(5)
- Eukaryotic Post-Translational Regulation(4)
- 17. Viruses(23)
- 18. Biotechnology(69)
- 19. Genomics(22)
- 20. Development(33)
- 21. Evolution(44)
- 22. Evolution of Populations(35)
- 23. Speciation(43)
- 24. History of Life on Earth(34)
- 25. Phylogeny(26)
- 26. Prokaryotes(35)
- 27. Protists(27)
- 28. Plants(43)
- 29. Fungi(26)
- 30. Overview of Animals(16)
- 31. Invertebrates(26)
- 32. Vertebrates(47)
- 33. Plant Anatomy(31)
- 34. Vascular Plant Transport(26)
- 35. Soil(31)
- 36. Plant Reproduction(29)
- 37. Plant Sensation and Response(40)
- 38. Animal Form and Function(43)
- 39. Digestive System(42)
- 40. Circulatory System(58)
- 41. Immune System(43)
- 42. Osmoregulation and Excretion(35)
- 43. Endocrine System(36)
- 44. Animal Reproduction(39)
- 45. Nervous System(41)
- 46. Sensory Systems(34)
- 47. Muscle Systems(31)
- 48. Ecology(47)
- Introduction to Ecology(47)
- Biogeography(0)
- Earth's Climate Patterns(0)
- Introduction to Terrestrial Biomes(0)
- Terrestrial Biomes: Near Equator(0)
- Terrestrial Biomes: Temperate Regions(0)
- Terrestrial Biomes: Northern Regions(0)
- Introduction to Aquatic Biomes(0)
- Freshwater Aquatic Biomes(0)
- Marine Aquatic Biomes(0)
- 49. Animal Behavior(35)
- 50. Population Ecology(51)
- Introduction to Population Ecology(51)
- Population Sampling Methods(0)
- Life History(0)
- Population Demography(0)
- Factors Limiting Population Growth(0)
- Introduction to Population Growth Models(0)
- Linear Population Growth(0)
- Exponential Population Growth(0)
- Logistic Population Growth(0)
- r/K Selection(0)
- The Human Population(0)
- 51. Community Ecology(51)
- Introduction to Community Ecology(0)
- Introduction to Community Interactions(24)
- Community Interactions: Competition (-/-)(0)
- Community Interactions: Exploitation (+/-)(0)
- Community Interactions: Mutualism (+/+) & Commensalism (+/0)(0)
- Community Structure(27)
- Community Dynamics(0)
- Geographic Impact on Communities(0)
- 52. Ecosystems(25)
- 53. Conservation Biology(59)
21. Evolution
Introduction to Evolution and Natural Selection
21. Evolution
Introduction to Evolution and Natural Selection: Study with Video Lessons, Practice Problems & Examples
26PRACTICE PROBLEM
Most of the mammals in Australia are marsupials (carry their young in their pouch), while most mammals elsewhere in the world are placental. What could explain this difference?
Most of the mammals in Australia are marsupials (carry their young in their pouch), while most mammals elsewhere in the world are placental. What could explain this difference?