2. Diversity & Classification

3. Objective A Students will define the criteria used for classifying organisms.

4. Understanding Biodiversity….  Scientists estimate that there are 5 million DIFFERENT kinds of plants, animals and microorganisms on earth.  Biodiversity: The variety of organisms in a given area.

5. What is taxonomy?  GROUPING things according to their CHARACTERISTICS.

6. Groups  Kingdom (largest)  Phylum  Class  Order  Family  Genus  Species (smallest) Great way to remember: Kids Play Chase On Freeway Get Squished

7. Kingdom  Encompasses large groups; such as plants, animals or fungi.

8. Phylum  Subgroup within a kingdom. Animals belong to the phylum Chordata. (meaning they have a spinal “chord”)

9. Class  A sub group within a phylum containing common characteristics.

10. Order  A sub group within a class.

11. Family  A sub group with an order.

12. Genus  A sub group within a family  Species with uniquely shared traits  Species are thought to be closely related.

13. Species  Unique group of organisms united by heredity or interbreeding  Defined based on unique features

15. Changes over time….  The classification system has changed over time  Traditionally used appearance and structure to group organisms  Can cause problems – some groups look similar but turn out to be distantly related others that look different are closely related

16. FYI: Example In a sense, birds are dinosaurs!  Scientists think that modern birds are descended from a subgroup of dinosaurs – theropods.  They base this information on comparisons of modern birds and fossilized theropods.

17. What’s in a name?

19. Creating Scientific Names  Carl Linnaeus – 1750’s  Catalog all known species  Created two-worded Latin names for each species (Binomial Nomenclature)

20. Binomial Nomenclature (bie NOH mee uhl Noh muhn KLAY chuhr)  Scientific Name = Binomial Nomenclature Genus + Species = Scientific Name Example = Humans Homo + Sapien = Homo sapien

21. Objective B Students will be able to utilize a dichotomous key to classify organisms.

22. We know that this cow is “Bos Taurus” but….. “How did we get there?”

23. The road to classification Requires – keys Dichotomous Keys

24. Dichotomous Key  Assists in Identification  Contains pairs of contrasting descriptions  The key directs the user to another pair of descriptors or  Identifies an object

25. Modern Linnaean System  Changes over time…  Category Domain – has been added (based on rRNA analysis)

26. 3 Broad Groups  Eukaryote –Multiple chromosomes and a mitotic cycle i.e. animals  Prokaryote –Single-Celled does not have nucleus or membrane-bound structures i.e. bacteria  Archaea –Prokaryotes in extreme environments difference in genetic make up of their cell call. i.e. bacteria in hot pots