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Chapter 25 Quizzes: Self Activities Chapter Cum.
Unit 4: Mechanisms of Evolution Phylogeny and Systematics Review
  1. is the study of the evolutionary history of species. is the study of the diversity and relationships of organisms, based on shared characters inherited from a shared .
  2. Some of the tools biologists use include the record, as well as and comparisons to infer evolutionary relationships.
    • Most of the record is found in layers of rock called .
    • similarity can be misleading due to evolution (analogy), when similar environmental pressures and selection produce similar (analogous) in organisms from different evolutionary lineages.
    • homologies that make use of computer programs to analyze segments can reveal many relationships not attainable by other methods.
  3. Carolus Linnaeus introduced a system, called , for classifying species in hierarchical categories (taxa): , , , , , , and . A level above kingdom called was added later.
  4. The scientific name of an organism uses nomenclature that uniquely identifies an organism in this hierarchy, and is composed of its and epithet; examples include Panthera pardus and Homo sapiens in the kingdom.
  5. Phylogenetic relationships are shown as branching trees where each branch point represents the of two when they shared a common . Shared ancestry and shared characters are drawn on a to show evolutionary relationships; this practice is called .
  6. A must be , and consists of the species and all its descendants. A group does not include all the descendants, while a group may include several organisms that lack a common ancestor. Clades are defined by an evolutionary novelty at the branching point, which constitues a shared character for the clade; an does not possess that character.
  7. The tree of life is divided into three great clades called : (Monera), , and .

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Chapter 26 Quizzes: Self Activities Chapter Cum.
Unit 5: The Evolutionary History of Diversity The Tree of Life Review
  1. The 4.6 billion years of earth's history is divided into three geologic , which are further divided into , , and .
  2. There have been several episodes of mass , when many forms of life disappeared, but they were replaced by forms that evolved from the survivors, and the general trend has been an of diversity over time.
  3. The (PT) extinction was the most severe, and claimed over 90% of marine species. The (KT) extinction is famous for the disappearance of , and was probably caused by the impact of a large .
  4. were Earth’s sole inhabitants from 3.5 to about billion years ago. The oldest known fossils are composed of layers of (blue-green algae) and , dating back billion years ago. Cyanobacteria were photosynthetic which released oxygen, allowing the evolution of organisms to obtain energy through cellular .
  5. The first eukaryotes probably evolved from the of small prokaryotes living within larger host cells and developing into organelles including and such as chloroplasts.
  6. Multicellular eukaryotes diversified in the late eon, when a severe age started to thaw. The first multicellular organisms were , collections of autonomously cells.
  7. Most of the major animal phyla, including the first , appeared during the early period in what is known as the Explosion.
  8. Plants first colonized land during the period in the company of , followed by . The relationships between plants and fungi are still common today in associations.
  9. Humans evolved from terrestrial vertebrates called , during the epoch. If the clock of Earth’s history were scaled to represent an hour, humans appeared about one ago.
  10. The movement of the Earth's due to continental has great impact on the habitats in which organisms live, and shaped the diversity of life on Earth.
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