Pre-Living Environment 2nd SEMESTER REVIEW

1. Lackawanna High School Pre-Living Environment2nd SEMESTER REVIEW June 2012

2. Relative dating Using index fossils that are found in layers of sedimentary rock to determine which layer is older than other layers 1.

3. Sedimentary rock Formed in layers; only type of rock to contain fossils 2.

4. Index Fossils Commonly found in sedimentary rock layers throughout the world; used for relative dating 3.

5. Radioactive elements Used to determine the absolute age of rock layers or fossils 4.

6. Information from fossils 2. Organisms have changed over time 1. Structural similarities 3. Some organisms have gone extinct 5.

7. Similar biochemistry 2. Organisms that are related have similar enzymes 1. DNA has similar sequences of bases (A, T, C, G) 6.

8. Similar body structures 2. Embryos are similar in early development 1. ex. Lion leg, bat wing, dolphin fin 7.

9. Divergent evolution Organisms of the same species evolve and become different species Ex.) different species of finches that Darwin found on the Galapagos Islands 8.

10. Convergent evolution Unrelated species develop similar traits because their environments are similar Ex.) dolphins and fish have similar body structues 9.

11. Co - evolution Two organisms evolve so that they function together in an ecosystem Ex.) Bees have body structures that are adapted to pollinate certain flowers; the flowers produce nectar to feed the bees. 10.

12. WHEN: 1831-1836 voyage and observations Who: CHARLES DARWIN WHERE: around the coast of South America to the Galapagos Islands WHAT: Theory of Natural Selection WHY: Data and observations indicated common ancestry HOW: observations of fossils and living organisms 11.

13. Natural Selection 2. Competition for resources 3. Variation of traits 1. Overproduction of offspring 4. Survival of the fittest – organisms that are unable to adapt go extinct 12.

14. Gene Pool All the genes in an entire population 13.

15. Adaptation A trait that helps an organism survive in its environment 14.

16. Evolution Process by which a species gradually changes over time 15.

17. Ecology The study of interactions between organisms and their environment 16.

18. Biotic living 17.

19. Abiotic nonliving 18.

20. Population All the members on ONE SPECIES in an environment 19.

21. Community All the members on ALL SPECIES in an environment 20.

22. Ecosystem all species (living, biotic) PLUS environment (nonliving, abiotic) 21.

23. Biosphere The part of the entire earth that supports life 22.

24. Habitat The environment that an organism is adapted to survive in 23.

25. Exponential growth population time 24.

26. Limiting factor something that stops a population from increasing beyond a certain number. Ex. Food supply, disease, space 25.

27. Carrying capacity The maximum number of a population that a habitat can support because of limiting factors population time 26.

28. Niche The specific role that an organism plays in its habitat 27.

29. Niche The specific role that an organism plays in its habitat 28.

30. Symbiotic relationship Two organisms live together so that at lest one depends on the other 29.

31. Parasitism Symbiotic relationship in which one organism benefits while the other is harmed. 30.

32. Commensalism Symbiotic relationship in which one organism benefits while the other is not affected at all 31.

33. Mutualism Symbiotic relationship in which both organisms benefit 32.

34. Producer / autotroph Organism that makes its own food by doing photosynthesis Gets energy directly from the sun Bottom of energy pyramid Beginning of food chain or web 33.

35. Consumer / heterotroph Organism that obtains food from other organisms Gets energy directly the level below it on the pyramid 34.

36. Herbivore Animal that eats only plants 35.

37. Carnivore Animal that eats only animals 36.

38. Omnivore Animal that eats both animals and plants 37.

39. Omnivore Animal that eats both animals and plants 38.

40. Decomposer / saprophyte Feeds off of dead organisms Helps nutrients recycle into the soil 39.

41. Food chain Shows energy flow through an ecosystem  means “is eaten by” or “energy is transferred to” Always starts with a producer 40.

42. Food web Many interrelated food chains 41.

43. Biodiversity Number of different species that exist in an ecosystem 42.

44. Introduced species Species that is brought to an ecosystem by humans May or may not disrupt the existing food webs and niches 43.

45. Introduced species Species that is brought to an ecosystem by humans May or may not disrupt the existing food webs and niches 44.

46. Conservation biology Study of ecosystems with the goal of preserving biodiversity 45.

47. Ecological Succession Each species of plants modifies the environment so that the next species can survive. See page 13 46.

48. Ecological Succession Each species of plants modifies the environment so that the next species can survive. See page 13 47.

49. Homeostasis Stable, constant internal conditions. All body systems work together to maintain homeostasis. 48.

50. Enzyme Protein molecule that helps break down (digest) food into usable molecules Specific shape Works best at a specific temperature 49.