1. Unit: Classification How are living things classified. SB3b
Unit: Classification How are living things classified? SB3b. Examine the evolutionary basis of modern classification systems

2. Unit: Classification How are living things classified. SB3b
Unit: Classification How are living things classified? SB3b. Examine the evolutionary basis of modern classification systems

3. How are living things classified?
Classification – grouping of objects, information, objects & organisms based on similarities

4. How are living things classified?
Taxonomy – grouping and naming of organisms(living things)
- Linnaeus developed the present method of classification
- classified organisms by their physical and structural similarities-THEN
 NOW-scientists use evolutionary relationships to classify organisms

5. How are living things classified?
Organisms are named using a ___2_____ - word system (scientific names)binomial nomenclature
Rules: Scientific names are always italicized or underlined
Scientific names are Latin
Scientific names are made of 2 words:
Genus name is the first word – it starts with capital letter
- species name is the __second_ word – it starts with a lowercase letter
Ex: Homo sapiens = Humans OR Ursus maritimus = Polar Bear

6. How are living things classified?
Organisms are classified ( organized) based on:
1) Physical similarities (ex: homologous structures)
2) Fossil evidence that show common ancestry
3) similarities in embryological stages (ex: embryos of different species have
tails & gills)
4) similarities in DNA and
proteins
(molecular biology/
biochemistry)

7. How are living things classified?
Linnaeus’ System of Classification
Linnaeus’ system has 7 taxa a.k.a. levels
( taxon – singular)

8. Taxon Pneumonic Example: Humans
 Kingdom _________________ Animalia
Phylum _________________ Chordata
Class _________________ Mammalia
Order _________________ Primate
Family _________________ Hominidae
Genus _________________ Homo
Species _________________ sapiens

9. How are living things classified?
** The more classification levels 2 organisms have in common, the more closely related they are
** The less classification levels 2 organisms have in common, the more __distantly___ related they are

10. 3 Domains of Life
Domains-more general than kingdoms

11. Sizes in biology

12. Are viruses classified?

13. Are viruses living? Growth No Yes Cells No Yes Homeostasis No Yes
Characteristic of Life Virus Cell
Growth No Yes
Cells No Yes
Homeostasis No Yes
Energy No Yes
Mutation Yes Yes
Nucleic Acid DNA or RNA DNA
Reproduction only within host cell independently by cell division
Structure DNA or RNA protein Cell membrane wrapped in protein cytoplasm, ribosomes