1. The Classification of Living Organisms
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2. Why classify things? Say you go to the mall to get some new clothes.
Where would you go?
How would you know to go to that particular store?

3. How is a mall organized? Food Court Big Department Stores
Specialty Clothing Stores
Jewelry Stores
Electronics Stores
Shoe Stores
Toy Stores
Kiosks

4. Can you imagine if the mall was just one big store and you had to go through rows and rows of “stuff” to find the right clothes in the right brand and the right size for you?
How long would that take?

5. Big Idea:
The mall, your city, your school, and your closet (hopefully) are all organized so that you and other people can get things done without wasting extra time and effort.
Scientists also organize or classify things so that they are easier to investigate and understand.

6. Classification Activity
FOOTWEAR!
Brainstorm 2 initial categories into which all footwear fall
Look at your shoes and place yourselves in one of the two groups
Write in flow-chart form below first two categories the second two.
1. (ie. boot/shoe; leather/cloth; heel/no heel; laces/no laces)
2. Write categories on board: one on left side at top, one on right side at top

7. Brainstorm 2 more categories into which all footwear from your group divides

8. One more time!
(there should now be 8 distinct groups)
Come up with a name for your species of footwear

9. Activity Wrap-Up
What difficulties did you have in coming up with categories or in determining which group you belonged to?
How might this apply to classification systems used by scientists in the field?
1. Ambiguities? (Shades of colour, different sizes, etc.)

10. Here are some things that scientists classify or organize:
The elements
The human body
Interactions in Ecosystems

11. Scientists also Classify Living Organisms
Cats, dogs, mammals, pets, friends………
How could you classify these living things?

12. Quick, organize these living things into groups:

13. Are there any other ways to group these living things?
Did you do it like this?
These are grouped by type of organisms: Fish, butterfly or bird
This is probably a more meaningful way to group these for scientific purposes than the previous slide’s grouping by color.
Are there any other ways to group these living things?

14. Or this?
These are grouped by color:
Blue, red or red and blue

15. Physical characteristics
Species Concepts
Morphological Species Concept:
Species compared based on
Body shape
Size
Structural features
Physical characteristics

16. Species Concepts Biological Species Concept: Fertile Offspring
Species determined based on
Similar characteristics
Ability to interbreed in natural circumstances and produce viable offspring
Fertile Offspring

17. Evolutionary relationships
Species Concepts
Phylogenic Species Concept:
Species compared based on
Evolutionary history
Relationships among organisms based on DNA analysis
Evolutionary relationships

18. Classification: Text p. 13, Activity 1.1: Snake or Lizard
-silent independent reading/brainstorming 4 mins
-share thoughts with partner 2 mins
What makes this type of classification `Morphological`?

19. The most basic classification system is based on Domains and Kingdoms
The most basic classification system is based on Domains and Kingdoms. Basic Classification Domains:
Archaea
There are three Domains of living organisms based on their characteristics:
Archaea (also called Archaebacteria)
Eubacteria (also called Bacteria)
Eukaryota (also called Eukarya)
Eubacteria
Eukaryota
The archaebacteria generally grow in extreme environments and have unusual lipids in their cell membranes and distinctive RNA molecules in their cytoplasm.
Eubacteria (True bacteria)
The presence of a nucleus gives eukaryotes their name, which comes from the Greek ευ (eu, "good") andκάρυον (karyon, "nut" or "kernel"). Most eukaryotic cells also contain other membrane-bound organelles such as mitochondria,chloroplasts and the Golgi apparatus. All large complex organisms are eukaryotes, including animals, plants and fungi. The group also includes many unicellular organisms.
Cell division in eukaryotes is different from that in organisms without a nucleus (Prokaryote). It involves separating the duplicatedchromosomes, through movements directed by microtubules. There are two types of division processes. In mitosis, one cell divides to produce two genetically identical cells. In meiosis, which is required in sexual reproduction, one diploid cell (having two instances of each chromosome, one from each parent) undergoes recombination of each pair of parental chromosomes, and then two stages of cell division, resulting in four haploid cells (gametes). Each gamete has just one complement of chromosomes, each a unique mix of the corresponding pair of parental chromosomes.

20. Organisms are classified into Domains or Kingdoms based on these characteristics:
1. Whether they are unicellular or multicellular 2. Whether they are prokaryotic or eukaryotic 3. Whether they have a cell wall or cell membrane 4. Whether they have membrane bound organelles 5. Whether they are autotrophic or heterotrophic 6. Whether they reproduce sexually or asexually 7. How they tolerate heat, salt, or other extreme conditions
See Vocabulary Activity in this Module.

21. Basic Classification Kingdoms: The Domains can also be split into Kingdoms which further divide the organisms by their characteristics. K I N G D O M S D O M A I N S

22. Kingdoms

23. “Archaea” means “ancient” bacteria. Organisms in Archaea are:
Domain Archaea
Aerial view of hot spring at Yellowstone
“Archaea” means “ancient” bacteria.
Organisms in Archaea are:
Unicellular
Prokaryotic
Autotrophic or heterotrophic
Organisms that reproduce asexually
Bacteria that have adapted to extreme environments.
Some can survive in extremely hot environments, like around hot springs and geysers. They are called thermophiles.
Some can survive in extremely salty environments, like The Great Salt Lake in Utah. They are called halophiles.
The Domain Archaea has one Kingdom, also called Archaea

24. This hot spring is flowing into the Firehole River in Yellowstone
This hot spring is flowing into the Firehole River in Yellowstone. The colors are caused by different varieties of archaebacteria and other microscopic life forms. Scientists can distinguish temperatures of water by the colors present.

25. Domain Eubacteria “Eu” means “true” bacteria. They are: Unicellular
Prokaryotic
Autotrophic or heterotrophic
Organisms that reproduce asexually
The most abundant organisms on earth. One bacterium can give rise to 10 million in 24 hours.
Found in almost every habitat on earth.
The Domain Eubacteria has one Kingdom, also called Eubacteria.
Many are common infectious agents.

26. This is a picture of bacteria on the skin
This is a picture of bacteria on the skin. Bacteria can be shaped like a sphere (cocci) like this picture, like a rod, or like a spiral. The structure in the middle of this picture is a hair follicle with a hair growing out of it.

27. Nucleus and Organelles
Terminology:
The Domains Archaea and Eubacteria are commonly grouped together in discussion and called
prokaryotes because they lack membrane-bound nuclei and membrane-bound organelles.
Nucleus and Organelles

28. Domain Eukaryota (Eukarya)
Eukaryotic
Very diverse
Unicellular or multicellular
Autotrophic or heterotrophic
Reproduce sexually or asexually
Can be split into 4 Kingdoms-
Protista
Fungi
Plantae
Animalia
The defining membrane-bound structure that differentiates eukaryotic cells from prokaryotic cells is the cell nucleus, within which the genetic material and many other cell bodies are contained. The presence of a nucleus gives eukaryotes their name that derives from the Greek (eu, "good") and (karyon, "kernel"). 

29. The 4 Kingdoms in Eukaryota
Protista
Mostly unicellular and microscopic
Autotrophic or heterotrophic
Can be infectious agents
Examples:
Amoeba
Algae
Daphnia
Plasmodium (causes malaria)
Plantae
Multicellular green plants
Autotrophic through photosynthesis
Have a cell wall
Mosses
Ferns
Trees
Flowering Plants
Fungi
Multicellular
Heterotrophic
Decomposers
Mushrooms
Athlete’s foot
Bread Mold
Animalia
Multicellular Animals
No Cell Wall
Insects
Spiders
Crabs
Birds
Humans

30. D O M A I N S K I N G D O M S

31. Taxonomic Classification: the answer to confusion
Binomial nomenclature: Binomial = 2 parts Nomenclature = naming system Species name composed of: 1: Genus name 2: Species name Eg. Homo sapiens (or Homo sapiens if handwritten) -Look at p. 15 in text

32. How would you classify these?
A organism that can exist in extremely hot temperatures and that is made of only one cell with no nucleus Domain: Archaea Kingdom: Archaea A green organism growing from the ground that is multicellular and that undergoes photosynthesis; its cells have nuclei and cell walls Domain: Eukaryota Kingdom: Plantae

33. Try two more:
This microscopic and one-celled organism lives in colonies with millions of others like it. It does not have a nucleus and cannot survive in extreme conditions. It could be an infectious agent. Domain: Eubacteria Kingdom: Eubacteria This organism is a multicellular decomposer; its cells have nuclei. Domain: Eukaryota Kingdom: Fungi

34. Classification Systems Can Change! Can you guess why?
Classification systems change as new organisms are discovered and as more information is gained about known living organisms.
Science is a “work in progress” and things change as new evidence is found.
There is a great amount of debate over the current classification system, especially the classification of the types of bacteria and whether viruses are alive or not.

35. Homework! Review pp. 8-23 in your textbook and answer
1.1 even questions
1.2, questions 1, 3, 5
Define: unicellular & multicellular
prokaryotic & eukaryotic
autotrophic & heterotrophic
sexual & asexual

36. Veterinarians classify organisms for many reasons:
Veterinarians have to classify infectious organisms so that they can understand how to treat them, according to their characteristics. It is important to know if they are bacteria, protozoa, prions, or viruses.
Veterinarians have to classify their patients so that they can understand how their patients’ body systems work and how to treat those systems. Different species, and even different breeds, react differently to treatment.
See Infectious Disease Lesson in this Module.

37. Which one would you choose? Why?
Even though classification is not an exact science, it is a part of almost every aspect of our lives.
This is an example of classifying by personal preference which all students have experience with.
Which one would you choose? Why?