Fall 2018
Freshman Year Emory College
Final Exam Review
● Characteristics of living things (activities mediated by biochemical activities within cells):
○ Ability to reproduce
○ Ability to respond to stimuli in environment
○ Take in nutrients/release waste
○ Maintain homeostasis
○ Growth and development
○ Adaptation: Populations evolve
○ Order and organization
● We are made mostly of water, about 66%
● 4 major biomolecules
○ Nucleic acids:
■ Catalysis
■ Storage of info
○ Proteins:
■ Catalysis
■ Structure
■ Communication
■ Transport
○ Carbohydrates
■ Energy storage
■ Structure
■ Identification
○ Lipids:
■ Energy storage
■ Membrane dynamics
■ Communication
● Darwin & Wallace
○ Darwin visited the galapagos islands
○ Mockingbirds gave first glimpse to evolution
○ Darwin and Wallace noticed a huge diversity of species
○ Many island species did not live anywhere else in the world
○ They saw variation and unclear species boundaries, sought a natural explanation
for their observations, and developed the theory of evolution through common
descent and natural selection.
○ Their theory is better supported today than ever before, and provides the
foundation of modern biology.
● Theory:
, ○ In science, a theory is not a hunch, but an explanation of an important feature of
nature supported by facts and verified by repeated observation and
experimentation.
● Common beliefs in Darwin’s (and Wallace’s) time
○ the earth was young (created 4004 BC)
○ species were created by God
○ species were perfect
○ species were fixed and did not vary (essentialism)
○ species did not change
● Darwin’s theories:
○ evolution as such (species change)
○ common descent
○ multiplication of species
○ Gradualism
○ natural selection (incl. Sexual selection)
○ In short: Descent with Modification
○ Put together: the gradual diversifying evolution of new species from common
ancestors through a process of natural selection
● Plato:
○ Typological thinking
○ Species are fixed and do not change
○ Special creation
● Aristotle:
○ Typological thinking
○ Scale of nature
● Lamarck:
○ Organisms originate through spontaneous generation, then evolve into higher
organisms over time.
● Darwin/Wallace:
○ Organisms have common ancestry and diversify over time.
● Necessary condition for evolution:
○ The earth is old
○ Charles Lyell: “Principles of Geology”
○ Uniformitarianism: Geological forces at the same rate in the past as they do now.
Implication: The earth is old
○ 4.5 billion years
● Evidence for Evolution:
○ (1) Biogeography / law of succession
○ (2) Artificial breeding
○ (3) Intermediate forms
○ (4) Imperfections
○ (5) Transition fossils
○ (6) Hierarchical Organizations
, ○ (7) Homology
○ (8) Vestigial traits
● Phylogenetic trees
○ Evolutionary tree
○ Diagrammatic depiction of organisms that are connected through common
descent.
○ Show evolutionary of organisms
○ Based on evolutionary relatedness
○ Taxa are more closely related to each other when they have a more recent
common ancestor
○ Cladogram: The only info is branching pattern and order; branch length provides
no info
○ Phylogram: Branch length indicates level of divergence
○ Monophyletic: Groups that contain all descendents of a particular ancestor
○ Phylogenetic trees based on homologous traits
○ Synapomorphy: Shared derived homologous trait.
○ Homologous traits can be genetic
○ Parsimony: Principle that the simplest scenario is the best one
○ Convergent evolution: process whereby organisms not closely related (not
monophyletic), independently evolve similar traits as a result of having to adapt to
similar environments or ecological niches.
● Bacteria
○ Cell wall
○ Membrane (unbranched fatty acids)
○ No nucleus
○ Unique RNA
● Archaea:
○ Cell wall
○ Membrane (branched hydrocarbon chains)
○ No nucleus
○ Unique RNA
● Eucarya
○ Cell wall sometimes present (plants)
○ Membranes (unbranched fatty acids)
○ Nucleus
○ Unique RNA
● Stromatolites:
○ Fossilized mats of billions of bacteria cells
○ Oldest found from 3.5 BYA by radioisotope dating
● Precambrian Era:
○ Earth’s formation to appearance of most animal groups
○ 4.6 billion years ago to 541 million years ago