Course: Biology Agricultural Science & Technology Unit: Diversity and Classification State Standard V: Students will understand that biological diversity is a result of evolutionary processes. State Objectives 3: Classify organisms into a hierarchy of groups based on similarities that reflect their evolutionary relationships. a. Classify organisms using a classification tool such as a key or field guide. b. Generalize criteria used for classification of organisms (e.g., dichotomy, structure, broad to specific). c. Explain how evolutionary relationships are related to classification systems. d. Justify the ongoing changes to classification schemes used in biology. Unit Objectives: A. Students will define the criteria used for classifying organisms. B. Students will be able to utilize a dichotomous key to classify organisms. Materials Needed (Equipment): Bags of candy or pictures of candy wrappers/ Student Activity Sheet #1 (1 per student) Dark Hershey Minis with nuts Dark Hershey Minis without nuts Milk Chocolate Minis with nuts Milk Chocolate Minis without nuts Strawberry/ Grape Jolly Ranchers Atomic Warheads Laffy Taffy Sour Skittles Facilities: Stop Watches for optional memorization game. Copies of What s in a Name? Worksheet (1 per student) Classroom LCD Projector/Overheads
Interest Approach: Provide each of the students with a handful of different types of candies or Student Activity Sheet #1 (if candy is not available). Have the students divide the pieces of candy into two groups based on like characteristics. For example: chocolate vs. non-chocolate. Now have them pick one of their two groups and divide it into two separate groups of like characteristics. For example: Sweet vs. sour. Have the students continue to divide the groups until they end up with one piece of candy that is unique from all the other pieces. Allow 2-3 minutes for this activity before class discussion. Possible solution to interest approach: Chocolate Non Chocolate Dark chocolate Milk Chocolate Hard candy Soft Candy With No nuts With nuts No nuts Sweet Sour Sweet Sour nuts Dark Hershey minis with nuts Dark Hershey minis without nuts Milk chocolate minis with nuts Milk chocolate minis without nuts Jolly Ranchers Atomic Warheads Laffy Taffy Sour Skittles Discussion: What makes that piece of candy unique from all the other pieces? How is the candy the same from the other pieces? Anticipated answers: shape, size, color, texture, smell, etc. Suggested Introduction Statement: Today we are going to look at how scientists use a similar process to identify plant, animals and all living organisms. Identifying plants and other organisms is used in many fields. For example, landscapers need to be able to put the specific plants in the ground, in the right place. It is much easier for people to make sure there is common meaning, and that they are referring to the same type of plant.
Objective A: Students will define the criteria used for classifying organisms. (Note: Students should be taking notes from this point forward) Curriculum (Content) (What to teach) Instruction (Methodology) (How to teach) Why classify living organisms? Who cares? A1. We care so that we understand and can discover and study the Earth s variety of species About 1.7 million species have been named with millions more undiscovered Understanding Biodiversity Scientists estimate that there are 5 million DIFFERENT kinds of plants, animals and microorganisms on earth. Biodiversity: is the variety of organisms in a given area. Discussion based off of above questions emphasis the amount of species etc. A1. PPT Slide 3 further discussion on the varieties and the importance of understanding the variety of the species in a community or ecosystem. Who has heard of the word Taxonomy? What does Taxonomy mean? What is Taxonomy? A2. GROUPING things according to their CHARACTERISTICS. A3: Groups (Linnaean System) Kingdom (largest) Phylum Class Order Family Genus Species (smallest) A2. PPT Slide 4 A3. PPT Slide 5 - (Memorization Option: to help students memorize grouping order have them find a partner to memorize them with and then have a class race to see who can say them in the right order the fastest) Great way to remember: Kids Play Chase On Freeway Get Squished
A4. Kingdom Encompasses large groups; such as plants, animals or fungi. A4. PPT Slide 6 Suggestion as you go through the group orders point out that they line of organisms is getting smaller and that different classification the groups belong to as it gets smaller (i.e. mammalian, carnivore, ursidae etc.) A5. A5. PPT Slide 7 Phylum Subgroup within a kingdom. Animals belong to the phylum Chordata. (meaning they have a spinal chord ) A6. A6. PPT Slide 8 Class A sub group within a phylum containing common characteristics. A7. A7. PPT Slide 9 Order A sub group within a class.
A8. A8. PPT Slide 10 Family A sub group with an order. A9. A9. PPT Slide 11 Genus A sub group within a family Species with uniquely shared traits Species are thought to be closely related. A10. A10. PPT Slide 12 Species Unique group of organisms united by heredity or interbreeding Defined based on unique features A11. A11. PPT Slide 13 Review of Linnaean System grouping process check for understanding why the picture goes from 7 organisms to one.
A12. Changes over time. Changes in 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 other that look different are closely related A12. PPT Slide 14 A13. A13. PPT Slide 15 In a sense, birds are dinosaurs! Scientists think that modern birds are descended from a subgroup or dinosaurs theropods. They base this information on comparisons of modern birds and fossilized theropods Deinonychus Cassowary What s in a name? (Maybe discuss where their names came from) A14. What s in a name? A14. PPT Slide 16 Have students randomly try to read the Scientific Names as they come up on the slide. A15.
A15. PPT Slide 17 show pictures of animals that match Scientific Names. (do not give the corresponding scientific name until after the students have completed column one and two of the worksheet below) A16. Worksheet A16. Worksheet What s in a Name A17. Creating Scientific Names Carl Linnaeus 1750 s Catalog all known species Created two-worded Latin names for each species A18. Binomial Nomenclature (bie NOH mee uhl Noh muhn KLAY chuhr) A17. PPT Slide 18 Additional Information Carl Linnaeus created a simpler and more consistent system in the 1750 s He wanted to catalog all known species Wrote books in which he used the polynomial system but added a twoword Latin name for each species A18. PPT Slide 19 Scientific Name = Binomial Nomenclature Genus + Species = Scientific Name Example = Humans Homo + Sapien = Homo sapien
Objective B: Students will be able to utilize a dichotomous key to classify organisms. Curriculum (Content) Instruction (Methodology) (What to teach) (How to teach) B1. We know that this cow is Bos Taurus but.. How did we get there? B1. PPT Slide 20 B2. The road to classification B2. PPT Slide 21 Requires keys What type of keys? A Dichotomous key! B3. Dichotomous Key B3. PPT Slide 22 Assists in Identification Contains pairs of contrasting descriptions The key directs the user to another pair of descriptors or Identifies an object B4. Modern Linnaean System B4 PPT Slide 23 Category Domain has been added (based on rrna analysis) 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 B4. Review/Assessment Computer Lab Activity B4. If available go to the computer lab and have the students go to the following web page and click on Classifying Life and complete the classification activities. http://www.pbs.org/wgbh/nova/orchid/classifyin g.html Evaluation: Diversity and Classification Test
Student Activity Sheet #1