Transcript Classification Notes

Classification
O. Complete a dichotomous key.
Agenda:
Notes
Shark key
Due at end of hour – no exceptions
This week.
Monday – Bacteria Flu Video
Tuesday – Classification/Chapter 17
Wednesday – Bacteria (microviewers)
Thursday – Bacteria and viruses
Friday – Test Chapters 17,23,24
Classification
O. Understanding why scientists classify organisms.
How easily would you be able to find a pair of
dirty socks in this room?
While watching video try to define
the following terms.
Binomial nomenclature
Taxonomy
Taxa
Genus
Species
O. I will know how to properly name an organism
by the end of the hour.
No journal
Remind me to tell you about group grade…
Truman State library!
Classification
 To
study the diversity of life, biologists use
a classification system to name organisms
and group them in a logical manner
 Taxonomy
is the discipline of classifying
organisms and assigning each organism a
universally accepted name
Development of a Classification
System

Carolus Linnaeusdeveloped a two word
naming system that is
still in use today
 In Binomial
Nomenclature each
species is always
assigned a two-part
scientific name
Now You Try
 Examples:
drosophilia melongaster
 homo sapiens
 canis familiaris


The first part of the scientific name is the
genus. The first letter of this name is always
capitalized--- Ursus

The second part of the scientific name is the
species, which is never capitalized
---- maritimus
Both names should be in italics or underlined
Ursus maritimus
What’s in a Name
 When
written together, the scientific name
includes both the species and genus name
of the organism
 This should be italicized when typed or
underlined when written hand-written
Practicing the use of a dichotomous key.
J. Write down your name and address as though
you were addressing an envelope.
Sally Sloth
7001 S. Hwy 94
Beautiful St. Charles, MO
USA
Identify what would be analogous to the taxonomic
Categories kingdom, phylum, class, order, family,
genus, species
Agenda
Practice making a dichotomous key
Vocabulary Exercise – get pumped!
Real Deal – make dichotomous key on
live organisms
Food Chain/Web
Taxonomic Categories
Linnaeus’s system of
classification uses 7
taxonomic categories.
 Genus is a group of
different species that
share common
characteristics
 We now have 8
categories

Kingdom
Phylum
Class
Order
Family
Genus
Species
Taxonomic Characteristics
 Families
are composed of different groups
of genera (genus) that share similar
characteristics
 Families are grouped into orders.
 Orders are grouped into classes.
 Classes are grouped into phyla (Phylum)
 Phyla (phylum) are grouped into a large
category called a kingdom
Chapter 17
Section 1 Biodiversity
Classification Hierarchy
of Organisms
Chapter 17
Section 2 Systematics
Objectives

Identify the kinds of evidence that modern biologists
use in classifying organisms.

Explain what information a phylogenetic diagram
displays.

State the criteria used in cladistic analysis.

Describe how a cladogram is made.

Discuss how proteins and chromosomes are used to
classify organisms.
Modern Evolutionary Classification

Aristotle first grouped organisms into groups
based on ground, air, water
 Linnaeus compared structure and anatomy
 Biologists now group organisms into categories
that represent lines of evolutionary descent, not
just physical similarities
 Derived Characteristics are those that “show
up” in newer parts of a lineage but are not in its
older members
Systematics – classification in terms of their natural
relationships; it includes describing, naming, and
classifying the organisms
Phylogenetics – analysis of evolutionary, or
ancestral, relationships between taxa
Cladistics – a phylogenetic classification system
that uses shared and derived characters and
ancestry as the sole criterion for grouping taxa
Clade – a taxonomic grouping that includes only a
single ancestor and all of its descendants
Chapter 17
Section 2 Systematics
Phylogenetics
A
modern approach to taxonomy is
systematics, which analyzes the diversity
of organisms in the context of their natural
relationships.
 When
classifying organisms, scientists
consider fossils, homologous features,
embryos, chromosomes, and the
sequences of proteins and DNA.
Chapter 17
Section 2 Systematics
Phylogenetics, continued
A
phylogenetic diagram displays how
closely related a subset of taxa are
thought to be.
Chapter 17
Section 2 Systematics
Phylogenetics, continued
Evidence of Shared Ancestry

Homologous features as well as similarities in
patterns of embryological development
provide information about common ancestry.
Chapter 17
Section 2 Systematics
Phylogenetic Diagram of
Mammals
Chapter 17
 Cladistics
Section 2 Systematics
Cladistics
uses shared, derived
characters as the only criterion for
grouping taxa.
Cladogram: Major Groups of Plants
Modern Evolutionary Classification
 Cladograms
are diagrams
that show
evolutionary
relationships
between
groups of
organisms
Chapter 17
Section 2 Systematics
Cladistics, continued
Molecular Cladistics

Molecular similarities (such as similar amino
acid or nucleotide sequences), as well as
chromosome comparisons, can help
determine common ancestry.
Chapter 17
Section 2 Systematics
Cladistics, continued
Chromosomes
Analyzing karyotypes can provide more
information on evolutionary relationships.
Chapter 17
Section 2 Systematics
Similarities in Amino Acid
Sequences
Chapter 17
Section 3 Modern Classification
The Tree of Life
Revising the Tree
The phylogenetic analysis of rRNA nucleotide
sequences by Carol Woese led to a new “tree
of life” consisting of three domains aligned
with six kingdoms.
Chapter 17
Section 3 Modern Classification
Three Domains of Life
 The
three domains are Bacteria, Archaea,
and Eukarya.
Chapter 17
Section 3 Modern Classification
Phylogenetic Diagram of Major
Groups of Organisms
Chapter 17
Section 3 Modern Classification
Three Domains of Life,
continued
Domain Bacteria

Domain Bacteria aligns with Kingdom
Eubacteria, which consists of single-celled
prokaryotes that are true bacteria.
Chapter 17
Section 3 Modern Classification
Three Domains of Life,
continued
Domain Archaea

Domain Archaea aligns with Kingdom
Archaebacteria, which consists of singlecelled prokaryotes that have distinctive cell
membranes and cell walls.
Chapter 17
Section 3 Modern Classification
Three Domains of Life,
continued
Domain Eukarya
Domain Eukarya includes the kingdoms
Protista, Fungi, Plantae, and Animalia.
All members of this domain have eukaryotic
cells.
Chapter 17
Section 3 Modern Classification
Six Kingdoms
Chapter 17
Section 3 Modern Classification
Kingdom and Domain
Characteristics
Chapter 17
Standardized Test Prep
Multiple Choice
1. Which information is given in a species
name?
A. genus and order
B. division and genus
C. genus and species identifier
D. species identifier and phylum
Chapter 17
Standardized Test Prep
Multiple Choice, continued
2. To which level of classification does a
group of closely related species of
organisms belong?
F. class
G. order
H. genus
J. kingdom
Chapter 17
Standardized Test Prep
Multiple Choice, continued
3. Eukaryotic organisms that have a nucleus
and organelles, have a cell wall made of
chitin, and secrete digestive enzymes
belong to which kingdom?
A. Fungi
B. Plantae
C. Protista
D. Animalia
Chapter 17
Standardized Test Prep
Multiple Choice, continued
Use the
cladogram to
answer
question 4.
The
cladogram
shows the
phylogenetic
relationships
Chapter 17
Standardized Test Prep
Multiple Choice, continued
4. On the basis of this cladogram, which
plants share the most recent common
ancestor?
F. mosses and ferns
G. mosses and pine trees
H. ferns and flowering plants
J. pine trees and flowering plants
Chapter 17
Standardized Test Prep
Multiple Choice, continued
Complete the following analogy:
5. class : order :: kingdom :
A. genus
B. domain
C. species
D. phylum
Chapter 17
Standardized Test Prep
Multiple Choice, continued
Use the diagram below to answer
question 6. The diagram represents
the eight levels of classification.
Chapter 17
Standardized Test Prep
Multiple Choice, continued
6. Which level of classification represents a
species?
F. A
G. C
H. D
J. G
Data used by systematics
 Morphology
 fossil
evidence
 embryology
 chromosomal similarities
 biochemical evidence
Phylogenetic Diagram
A
branching diagram showing the
evolutionary relationships among a group
of organisms
Modern Evolutionary Classification
 The
genes of many organisms show
important similarities at the molecular
level. These similarities can be used as
criteria to help determine classification
 All organisms use RNA and DNA to pass
on information. All organisms use ATP as
an energy-carrying molecule. Similarities
in other important chemicals give us
another way to compare them
Modern Evolutionary Classification
 Molecular
clocks use DNA comparisons to
estimate the length of time that two
species have been evolving
independently. This relies on the rate that
neutral mutations accumulate in the DNA
of different species
Kingdoms and Domains
 Using
new tools available today, scientists
have expanded upon Linnaeus’s system of
classification.
 The 6 kingdom system of classification
includes the kingdoms Eubacteria,
Archaebacteria, Protista, Fungi, Plantae,
and Animalia
Kingdoms and Domains
 Today,
most scientists are now
recognizing molecular evidence that
requires the addition of a category even
larger than kingdom: the domain
 Domains:



Archaea
Bacteria
Eukarya