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					Evolution

Standard 12.4.3
                        Mutations
   Types of Mutations:
       chromosomal
            deletions, duplications, inversions, translocations
       gene
            point and frameshift
   Effects of Mutations:
       alter chromosome number
       change amino acid sequences
   Polyploid: 3 sets of chromosomes, usually
    fatal in animals... plants like
                     Breeding

   Types of Selected Breeding:
       hybridization: crossing different organisms
       inbreeding: crossing alike organisms

   Effects of Breeding:
       can produce better fit offspring
       can ensure that specific traits are carried on
       can cause birth defects in animals
             Speciation

 When similar organisms live in the same
  area they may become more alike
 When similar organisms breed during
  the same mating season they may
  become more alike
 Example: Frogs
Frog Breeding Seasons
          Cell Transformation
   cell transformation: insertion of new genes
    into a cell that changes the genetic makeup
   Prokaryotes:
       have plasmids: circular DNA
       other bacteria can "ingest" plasmids and take on
        new DNA from another bacteria...remember the
        mice?
   Eukaryotes:
       DNA is taken out with tiny needles and implanted
        into other cells
       unicellular organisms have plasmids
    Structures of Organisms
   Homologous Structures: body parts that
    develop from similar tissues early on, same in
    structure and function
   Analogous Structures: structures that have
    different structures but same function:
    butterfly wing and bird wing
   Vestigial Structures: Left over structures that
    no longer server a purpose: example
    appendix
Homologous Structures
Analogous Structures
Vestigial Structures
                  Selection

   Convergent Radiation
       Unrelated organisms change overtime
        because of environment
       Examples: wing, skinny beaks
   Adaptive Radiation
       Related organisms change overtime due to
        needs dictated by the environment
    Mechanisms of Evolution

 Variation
 Inheritance
 Selection
 Time
                  Variation

   In all species, individuals differ in their
    genetic makeup, producing many
    variations in their physical features
             Inheritance

 Individuals pass some of their genetic
  material on to their offspring
 Gametes: sperm and egg
               Selection

 Some individuals have genes that help
  them survive better or produce more
  offspring
 Offspring are more likely to survive if
  genes that are good become more
  common
                 Time

 Over time, selection results changes in
  species
 Changes may take days or years or
  millions of years
                           HIV

                                  Inheritance: HIV invades
Variation: HIV carries
                                  human cells and tricks them
proteins on its surface. As the
                                  into making copies of the
genes change, the surface
                                  virus. Each time this happens,
changes; allowing it to infect
                                  the virus gets some genes
new hosts
                                  from the old virus
Selection: Some HIV can
dodge the immune system in
                                  Time: HIV can evolve with in
humans. The ones that do
                                  a single day.
are able to reproduce with
better characters
                     Human

Variation: Because       Inheritance: Humans
humans with longer       reproduce sexually and
legs can walk farther,   each organism receives
this is a desirable traithalf of their genes
                         from each parent
Selection: Since         Time: Humans and
humans live in different chimps share a
habitats, different      common ancestor that
characters are needed is 5-6 billion years old
to survive
Theories of Evolution (Ch 15)

   Darwin: Natural Selection
       Organisms change because they must in
        order to survive an environment
       Organisms that cannot survive in the new
        environment, die
       Survivors continue to breed and pass on
        genetic traits
Four Characters of Darwin
      pages 380-386
   Living Diversity: Organisms are varied, many
    characteristics
   Adaptation: Characters and behaviors of
    organisms can change to fit environment
   Evidence: Used fossil evidence for support,
    lots of organisms have come and gone
       Law of Superposition: location of layers of rock
   Fitness: the ability of an organism to
    reproduce and survive
   Darwin did not take into account the genetic
    make up of organisms (genes)
Theories of Evolution (pg 376)

   Lamark: Inheritance of acquired traits
       Besides environment and need for
        adaptation, the chance of inheriting traits
        that may or may not be beneficial occur
       Chances are the organism may die or
        survive dependant on the trait
                Diversity of Life

   Need for                Hierarchical system
    classification          Broad to specific
   Early systems           Kingdom to species
       Aristotle
       Linnaeus
   Binomial
    nomeclature
     Classification System

 Kingdom
 Phylum
 Class
 Order
 Family
 Genus
 Species
                    Examples

   Human                  Domestic Cat
       Animalia               Animalia
       Chordates              Chordates
       Mammalia               Mammalia
       Primates               Carnivora
       Hominidae              Felidae
       Homo                   Felis
       Sapiens                Domesticus
   Homo sapiens           Felis domesticus
                        Examples

   Cardinal                   Alligator
       Animalia                   Animalia
       Chordates                  Chordates
       Aves                       Sauropsida
       Passeriformes              Crocodilia
       Cardinalidae               Alligatoridae
       Saltator                   Alligator
       Atriceps                   Sinensis
   Saltator atriceps          Alligator sinensis
           Classification of
          Organisms: Linneaus
   Dichotomous Keys
       Used to figure out what an organism may be
       Has step by step directions and descriptions that
        help identify objects
   Organisms have a Latin binomial or scientific
    name
       Contains the genus and species name
       Italicized or underlined, not both
       First name is capitalized, second is not

				
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