23 4. Cyanobacteria were important because: They changed Earth’s atmosphere by adding free O2 to the air. The ozone layer formed protecting organisms from UV rays. Single-celled organisms evolved into complex organisms.
24 Invertebrate- animal without a backbone. Appeared: near the end of the Precambrian.Ex: jellyfish, sponges, worms
31 Paleozoic – “ancient life”. Life-forms that were most abundant during the Paleozoic- ocean dwelling (marine ) organisms.Why? Warm, shallow seas covered most of the Earth.Ex: trilobites, brachiopods, cephalopods, crinoids.
55 7. Archaeopteryx had wings and feathers like a bird, but teeth, claws and a tail like a dinosaur.
56 8. Mammals first appeared in the Triassic Period.
57 9. Traits allowing mammals to survive: 1. Hair or fur covering their bodies.
58 2. They are warm-blooded.3. Produce milk to feed their young.
59 10. Gymnosperms – "naked seed plant", no fruit covering their seeds.
60 First appeared: Devonian Period Ex: ferns, palms, ginkgos, pines
61 11. Angiosperms – flowering plants 11. Angiosperms – flowering plants. Produce seeds with a hard outer covering and/or fruit.First appeared: Early Cretaceous Period
62 Ex: fruits, vegetables, flowers, flowering trees
63 11. The end of the Mesozoic Era was marked by: Break-up of Pangaea, seas drained from lands, extensive volcanism, extinction of dinosaurs.
64 12. Cenozoic – "Recent Life"aka "Age of Mammals"
65 13. The Alps in Europe form from collision between African and Eurasian plates.
66 14. The Himalaya Mountains formed from the collision between the Indian and Eurasian plates.
67 15. Placental mammals – nourish their young internally from a placenta 15. Placental mammals – nourish their young internally from a placenta. Offspring born live & independent.First appeared: Cretaceous Period
76 18. Homo sapiens first appeared about 500,000 years ago. Homo sapiens neanderthalensis appeared about 250,000 years ago.Homo sapiens sapiens appeared about 100,000 years ago.We see the emergence of specifically human activities, such as art and religion.
77 19. Humans have been the dominant life form for the past 10,000 years. Starting about 10,000 years ago, agriculture, the domestication of animals, cities, and writing soon followed.