Classification O Complete a dichotomous key Agenda 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 Ø To study the diversity of life, biologists use a classification system to name organisms and group them in a logical manner Ø 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 Ø In Binomial Nomenclature each species is always assigned a two-part scientific name Ø

Now You Try Ø Examples: drosophilia melongaster l homo sapiens l canis familiaris l

Ø Ø 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 Ø When written together, the scientific name includes both the species and genus name of the organism Ø 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. Ø Genus is a group of different species that share common characteristics Ø We now have 8 categories Ø Kingdom Phylum Class Order Family Genus Species

Taxonomic Characteristics Ø Families are composed of different groups of genera (genus) that share similar characteristics Ø Families are grouped into orders. Ø Orders are grouped into classes. Ø Classes are grouped into phyla (Phylum) Ø 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 Ø Identify the kinds of evidence that modern biologists use in classifying organisms. Ø Explain what information a phylogenetic diagram displays. Ø State the criteria used in cladistic analysis. Ø Describe how a cladogram is made. Ø Discuss how proteins and chromosomes are used to classify organisms.

Modern Evolutionary Classification Ø Ø 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 Ø A modern approach to taxonomy is systematics, which analyzes the diversity of organisms in the context of their natural relationships. Ø When classifying organisms, scientists consider fossils, homologous features, embryos, chromosomes, and the sequences of proteins and DNA.

Chapter 17 Section 2 Systematics Phylogenetics, continued Ø A phylogenetic diagram displays how closely related a subset of taxa are thought to be.

Chapter 17 Section 2 Systematics Phylogenetics, continued Ø Evidence of Shared Ancestry l 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 Section 2 Systematics Cladistics Ø Cladistics uses shared, derived characters as the only criterion for grouping taxa.

Cladogram: Major Groups of Plants

Modern Evolutionary Classification Ø Cladograms are diagrams that show evolutionary relationships between groups of organisms

Chapter 17 Section 2 Systematics Cladistics, continued Ø Molecular Cladistics l 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 Ø Chromosomes l 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 Ø Revising the Tree l The phylogenetic analysis of r. RNA 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 Ø 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 Ø Domain Bacteria l 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 Ø Domain Archaea l 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 Ø Domain Eukarya l l 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 Ø Morphology Ø fossil evidence Ø embryology Ø chromosomal similarities Ø biochemical evidence

Phylogenetic Diagram Ø A branching diagram showing the evolutionary relationships among a group of organisms

Modern Evolutionary Classification Ø The genes of many organisms show important similarities at the molecular level. These similarities can be used as criteria to help determine classification Ø 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 Ø 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 Ø Using new tools available today, scientists have expanded upon Linnaeus’s system of classification. Ø The 6 kingdom system of classification includes the kingdoms Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia

Kingdoms and Domains Ø Today, most scientists are now recognizing molecular evidence that requires the addition of a category even larger than kingdom: the domain Ø Domains: l l l Archaea Bacteria Eukarya