Chapter 17 Classification

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Chapter 17 Classification
Information from Holt Biology other sites as
listed
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Why is classification necessary?
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• Are you an organized person?
• Consider do you organize your room? Your
  clothes? Your school work? CDs?
• What would happen if nothing was organized?
• Would you be able to find anything?

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• Scientists have identified more than
• 2 MILLION SPECIES!!!
• Every year, thousands of new species are
  discovered.
• There may be millions of undiscovered species
• especially microbes, plants insects
• In the Tropical Rain Forest Oceans
• Classification helps scientists understand
  study living things.

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I. Biodiversity

• Biodiversity is the variety of organisms on the
  earth.
• Considered at all levels from populations to
  ecosystems.

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A. Taxonomy

• Taxonomy is the science of describing, naming,
  and classifying organisms.
• The branch of biology that names groups
  organisms -according to their characteristics
  evolutionary history.
• A Universal System was designed to Eliminate the
  use of Common Names and Confusion in the
  Scientific World.

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The History of Taxonomy

• Aristotle a Greek philosopher who lived more
  than 2,000 years ago
• Classified things- Plant or Animal
• Grouped Animals into Land Dwellers, Water
  Dwellers, and Air Dwellers.
• Also grouped Plants into 3 categories, based on
  differences in their Stems.

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Aristotles classification system was replaced

• As modern science Aristotle's system was found to
  be
• INADEQUATE.
• Aristotle's categories
• did not work for
• all organisms.
• his use of common names
• was problematic.

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Use of Common Names

• COMMON NAMES, such as robin or fir tree, for
  organisms created some problems
• common names varied from one locale to next
  did not describe species accurately.
• Use of long Latin names
• Used by scientists before 1700s,- did not show
  relationships between species were
  inconvenient, hard to understand.

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Describe a problem with each of these common
names

• -Starfish -Seahorse -Jelly fish
• -Peanut -Catfish -Tiger shark
• How are their names misleading?

Discuss problems when 1 organism has 2 common
names
Example- firefly lightening bug
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Carl Linnaeus (1707-1778)

• Father of Modern
• Taxonomy
• He used morphology
• (which is the organisms
• structure form)
• Grouped organisms
• into hierarchical categories

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Carl Linnaeus

• Formed Taxa (groups of organisms)
• (Used Latin for the Names because it was the
  language of educated people)
• Morphology -the STRUCTURAL SIMILARITIES BETWEEN
  ORGANISMS
• Series of hierarchical categories used to show
  relationships
• He had 2 KINGDOMS PLANTAE ANIMALIA.

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B. Modern classification system is based on
morphological similarities.

• Hierarchy of eight groups (Taxa)
• Domains- include all six kingdoms
• Kingdom a taxon of similar phyla or divisions
• Phylum (phyla-plural)- taxon of similar classes
• Class taxon of similar orders
• Order taxon of similar families
• Family group of similar genera
• Genus group of similar species
• species most exclusive, specific group. Members
  of this grouping can mate, produce viable
  offspring
• (varieties) same species but with slight
  differences
• (subspecies) same species, different location

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8 Modern Levels of Classification (From the
most general to the most specific)

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
• Species- is the smallest, most specific group-
  contains only 1 kind of organism.

You need to know these!
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Taxon - A particular group in a taxonomic system
Most specific Taxon (group)
Most general taxon
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Pneumonic Devicespick one to help you remember
the taxa

• Keep Penguins Cool Or Find Good Shelter
• or
• Kennywood Park Can Open For Good Summers.
• or
• King Phillip Comes Over For Good Spaghetti

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Classification Hierarchy of Organisms
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3 Domains

• (Most modern level by scientist Carl Woese)
• These are Broad groups above the kingdom level.
• Archaea
• Bacteria
• Eukarya

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Binomial Nomenclaturemeans Two Name Naming

• Uses the last 2 categories (the most specific) to
  name things. uses the Genus Species for the 2
  parts of the name
• Always Capitalize the Genus but Not the Species
  Identifier.
• Both are either underlined or italicized.

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Using Binomial Nomenclature

• Acer rubrum - RED MAPLE TREE
•   Acer is the Latin name for Maple (genus)
•   rubrum is the Latin word for Red(species)
•   Can be Abreviated A.rubrum.
• Homo sapiens - HUMANS
• Homo -large brain upright posture. sapiens for
  our intelligence ability
• to speak. Abbreviated H. sapiens

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Additional Categories

• Zoologists
• use term SUBSPECIES for variations that may
  occur in species from different geographical
  locations- ie, timber wolf and the northern
  timber wolf- ex Canis Lupus ssp occidentalis
• Botanists
• May use the term division instead of phylum
• sometimes split species into Subsets known as
  VARIETIES. Example peaches nectarines are
  varieties of Prunus persica var.

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Additional Categories

• Microbiologists- Bacteria are also broken into
  subsets called STRAINS. Example Escherichia
  Coli some strains are harmless, even helpful-
  live in our intestines, but strain E. coli 157
  is responsible for food poisoning deaths.

According to the CDC there are an estimated
73,000 cases of E. Coli infection every year in
the United States. The typical symptoms are
bloody diarrhea and (if severe) kidney failure.
These symptoms most commonly appear when a person
has eaten undercooked or contaminated ground
beef.
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Testbook Assignment

• Read chapter 17, section 2
• do end of section questions
• Define
• Systematics
• Phylogeny
• Phylogenic Trees
• Embryology, -blastula, -gastrula
• Cladistics
• derived characters,
• cladogram

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The way we group organismscontinues to
changeToday these methods reflect the
evolutionary history of organisms (Whats in
their genes).This is called Phylogeny.
II. Systematics
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A. Phylogeny

• organizes the diversity of living organisms in
  the context of evolution.
• are based on several types of evidence
• Fossil Record
• Morphology
• Embryology
• Chromosomes Macromolecules

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Phylogenic Trees

• A family tree that shows evolutionary
  relationships thought to exist among organisms.
• Is a hypothesis about the relationships.
• Is subject to change - as more evidence is
  learned.

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1. Fossil Record
II. Evidences for Evolutionary Relationships

• a useful tool for ancient organisms.
• Record is incomplete
• Some organisms overrepresented
• Some organisms may be missing
• Need other evidences to verify phylogenic
  relationships

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Fossils Types actual preservation,
petrification, imprints, molds, casts, footprints

• Dated by radioactive isotopes in fossil or
  geological formation in which fossils are found
• Requires long periods
• of time and unusual conditions for fossil
  preservation

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2. Morphology
II. Evidences for Evolutionary Relationships

• Examine structure function
• Homologous structures- similar features that
  originated from similar ancestors. (forelimbs on
  bat, human, penguin)
• Analogous structures- features that serve similar
  functions look alike but originated from
  different embryonic tissues.
• (wings- on butterfly, bat, hummingbird)
• Vestigial structures -serve no useful function
  any longer in the organism

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Homologous structures
Comparing the structural features found in
different organisms reveals a basic similarity.
example is the forelimb of mammals - Although
function is quite different, they are similar
structurally.
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Analogous structures

• We must look at structures that look function
  the same but are not derived from the same
  embryonic tissue.
• These features do not show recent, related
  ancestory.

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Vestigial structures

• Features which serve no useful function any
  longer in the organism.
• Examples the pelvis bone in the whale, tailbone
  appendix in humans, pelvis leg bones in some
  snakes, etc

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Embryology
II. Evidences for Evolutionary Relationships

• SIMILARITIES IN EARLY EMBRYOLOGICAL DEVELOPEMNT
  OF VERTEBRATES
• CAN BE TAKEN AS ANOTHER INDICATION THAT
  VERTEBRATES MAY SHARE A COMMON ANCESTOR.

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At the blastula stage, scientists begin to look
for differences in the ways organisms develop.
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Blastula - An early embryonic form produced by
cleavage of a fertilized ovum - a spherical layer
of cells surrounding a fluid-filled cavity.(think
of a basketball) Gastrula - double-walled stage
of the embryo succeeding the blastula the outer
layer of cells is the ectoderm and the inner
layer differentiates into the mesoderm and
endoderm
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Embryology example-

• At the blastula stage- what happens if a
  scientist separates a cell from the ball?
• In Vertebrates (animals with a backbone)
  Echinoderms animals like starfish sand
  dollars)- any cell separated can produce a
  twin.
• But blastula cells in a fruit fly cannot- the
  separated cells are already specialized to form a
  part will die.
• Conclusion- we are more closely related to
  starfish than insects

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4. Chromosomes Macromolecules
II. Evidences for Evolutionary Relationships

• Taxonomists compare Macromolecules like DNA, RNA
  Proteins.
• Example- the number of differences in amino acids
  is a clue to how long ago 2 species Diverged
• Divergent Evolution- 2 species become more and
  more dissimilar.
• Convergent Evolution- Species which have
  different ancestors, but have become more similar

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Proteins indicate degree of relatedness.
Differences - Amino Acids in Protein Cytochrome C
Number of different amino acids found in human cytochrome C as opposed to selected organisms Number of different amino acids found in human cytochrome C as opposed to selected organisms Number of different amino acids found in human cytochrome C as opposed to selected organisms
 Organism of amino acids different compared to humans
Human 0 Self (Family Hominidae, Order Primates)
Monkey 1 Different family (Pongidae), same order (Primates)
Pig, bovine, sheep 10   Different order (Carnivora), same class (Mammalia)
Horse 12   Different order (Carnivora), same class (Mammalia)
Dog 11   Different order (Carnivora), same class (Mammalia)
Rabbit 9   Different order (Carnivora), same class (Mammalia)
Chicken, Turkey 13 Different class (Aves), same phylum (Chordata) - homeothermic
Duck 11 Different class (Aves), same phylum (Chordata) - homeothermic
Rattlesnake 14 Different class (Reptilia), same phylum (Chordata) - poikilothermic
Turtle 15 Different class (Reptilia), same phylum (Chordata) - poikilothermic
Tuna 21 Different class (Ostheichthys), same phylum (Chordata) - poikilothermic
Moth 31 Different phylum (Arthropoda), same Kingdom (Animalia)
Candida fungus 51 Different Kingdom (Fungi)
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Section 17.2 Summary pages 450-459
Chromosome comparisons

• For example, cauliflower, cabbage, kale, and
  broccoli look different but have chromosomes
  that are almost identical in structure.

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Martin (1993).
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B. Cladistics

• uses shared, derived characters as the only
  criterion for grouping taxa.
• Shared character - A feature that all members of
  a group have in common
• Derived character - A feature that evolved only
  within the group under consideration
• is a newer way to display relationships

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• Derived Characters- are special features that
  apparently have only developed in that group.
  Examples
• feathers in birds
• larger brains. Homosapiens
• have larger brains than the
• 'outgroup' (monkeys). The larger brain of
  homosapiens is a derived characteristic.
• Clade A Group of organisms that includes an
  ancestor plus all of its descendants

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Cladogram

• Diagrams which show derived characters
• Shared derived characters are strong indicators
  of common ancestry.
• Cladograms can show non-traditional conclusions
  about
• which organisms
• are close cousins.

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Cladogram
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From this cladogram, we can figure out that brown
bears have more derived characters in common with
sun bears than with dogs lesser pandas are more
closely related to racoons than giant pandas.
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Linnaean Taxonomy - compared to Phylogenetic
Nomenclature

• Linnaean Taxonomy - Primary goal is to group
  species based on morphological similarities (who
  has 6 legs)
• Phylogeny- Primary goal is to reflect the process
  of evolution (whos close cousins)

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Dichotomous Key

• graphically organizes data.
• You start with a main idea, split that into two
  major pieces.
• Those pieces are then split again into two major
  pieces. You continue splitting until you reach
  only one possible answer.
• Each set of questions is called a couplet,
  contains instructions for which couplet to go to
  next.

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Example of Dichotomous Key
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Dichotomous Key Use

• Can be used by any one to classify anything.
• Are used by taxonomists to classify organisms.

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III. Taxonomic Groups3 domains, 6 kingdoms

• 1. Domain Archaea
• aligns with Kingdom Archaebacteria, are
  single-celled prokaryotic cells that have
  distinctive cell walls are ancient bacteria
• 2. Domain Bacteria
• aligns with Kingdom Eubacteria, are single-celled
  prokaryotic cells that are true bacteria.
• 3. Domain Eukarya
• Domain Eukarya includes the kingdoms Protista,
  Fungi, Plantae, Animalia.
• All members of this domain have eukaryotic cells.

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• SIX KINGDOMS GROUP ORGANISMS TOGETHER THAT HAVE
  SIMILARITIES SUCH AS MAJOR CELLULAR STRUCTURE,
  METHODS OF OBTAINING NUTRIENTS, AND METABOLISM.

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A closer look at each of the 6 kingdoms
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Domain Archaea, kingdom Archaeavs.Domain
Bacteria, Kingdom Eubacteria

• Organisms in the Kingdoms Eubacteria Archaea
  are very different from each other, both
  genetically biochemically!
• Archaea have been found in temperatures above the
  boiling point and in cold that would freeze your
  blood.
• Eubacteria are the regular bacteria.

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Domain Archaea, Kingdom Archaea 1. Archaea

• archae- from the Greek for "ANCIENT".Scientists
  think these are similar to Earths First
  Organisms
• Extremophiles Many types of Archaeans live
  in HARSH ENVIRONMENTS
• Some types are
• Methanogens
• Themoacidophiles
• Extreme Halophiles

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Methanogens

• Live in ANAEROBIC
• Environments,
• Produce Methane
• Gas, a byproduct of
• metabolism in conditions of very low oxygen
• Includes Chemosynthetic Bacteria.
• Lives in the Intestines of Mammals.
• Methanobrevibacter smithii is the prominent
  methanogen in the human gut, where it helps
  digest polysaccharides (sugars).

http//www.nature.com/nrgastro/journal/v8/n10/full
/nrgastro.2011.159.html
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Thermoacidophiles - living in Sulfurous Hot
Springs Volcanic VentsThey loveacid
heat
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Extreme HalophilesLive in Very Salty Places
(like the great Salt lake the Dead
Sea)(Halite is the mineral name for NaCl)
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2. true or Eubacteria
Domain Bacteria, Kingdom Eubacteria

• The first thing you probably think of when you
  say this word is disease- something like strep.
  throat or maybe an infection in a cut.
• Most of the bacteria that are disease causing are
  Eubacteria.
• NOTE Only about 1 of bacteria are disease
  causing.

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Domain Bacteria, Kingdom Eubacteria

• Many bacteria are very helpful organisms.
• Actinomycetes, produce antibiotics such as
  streptomycin and nocardicin
• others live symbiotically in the guts of animals
  (including humans) or elsewhere in their bodies,
  or on the roots of certain plants, converting
  nitrogen into a usable form.
• Bacteria put the tang in yogurt and the sour in
  sourdough bread
• help to break down dead organic matter make up
  the base of the food web in many environments.

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True Bacteria
Domain Bacteria, Kingdom Eubacteria

• So remember- Most bacteria are beneficial
• Benign (benign good, friendly, kind)
• Pathogens (means disease causing -only a few are
  bad guys)
• Bacteria occur in 3 basic shapes cocci, bacilli
  spiral. Many are named by their shape.

biology.clc.uc.edu
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Examples of common bacteria
Lactobacillus acidophilus
Streptococcus pneumoniae
Escherichia coli
answersingenesis.org
http//www.oley.org/lifeline/Probiotics.html
genome.microbio.uab.edu
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3. Protists
Domain Eukarya, Kingdom Protista

• Made of a variety of organisms that dont fit
  anywhere else. (Some are not very much like the
  others in this group.)
• EUKARYOTIC (has a true nucleus)
• 50,000 species- many unicellular, some are like
  fungi, some like plants or animals.
• Includes protozoans, unicellular algae, slime
  molds water molds

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Examples of Protists includes slime molds
protozoans like Euglena, Paramecium, Ameoba
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4. Fungi
Domain Eukarya, Kingdom Fungi

• Can be Unicellular or multicellular
• HETEROTROPHIC (eats something else)
• NOT like plants (photosyntheic) (this is why they
  were kicked out of the plant kingdom)
• 100,000 species of mushrooms, puffballs, rusts,
  mildew molds

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Fungi Examples
Agaricus bisporus The Button Mushroom
Stink horn
Candida albicans- can cause yeast Infections-
like this mouth thrush
fcps.edu
reference.medscape.com
http//www.mushroomexpert.com/agaricus_bisporus.ht
ml
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5. Plantae
Domain Eukarya, Kingdom Plantae

• Multicellular
• Photosynthetic (Autotrophs) (They make their own
  food are the chief food producers of the
  world.)
• Found in all the types of environments aquatic
  algae, amphibian mosses, and terrestrial ferns
  and seed-bearing plants.
• 350,000 species identified.

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Types of plants
http//plantspages.com/typesofplants.htm
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Cladogram of the plant kingdom
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6. Animalia
Domain Eukarya, Kingdom Animalia

• Eukaryotic,
• Multicellular
• Heterotrophic
• Most animals are symmetrical
• Movement at some time in their life cycle.

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Examples of animals
biology.kenyon.edu
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What is on the ch 17 test?

• 1-6 Matching the 6 kingdoms or 3 domains with
  the correct description.
• 7-40. Multiple choice. Review you notes. Know
  the classification groups, the correct way to
  write binomial nomenclature the morphology
  terms (homologous, analogous, vestigial
  structures) phylogenic tree info.
• 41-50. True/ False
• 10-55. short answer.

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Practice these short answer questions for the
test

• Write a pneumatic devise to remember the
  classification categories, in order (this can be
  one we used in class or your own)
• What are the 6 kingdoms recognized today?
• What do plants fungi have in common with
  animals?

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You can do online flash cards for the vocab in
this chapter at

• http//quizlet.com/2096160/chapter-17-classificati
  on-flash-cards/