1. 18-3 Kingdoms and Domains

2. As biologists learned more about the natural world, it became apparent that Linnaeus’s 2-kingdom system was too simple.
Today, we use 6 Kingdoms for classification:
1. Plants (Plantae)
2. Animals (Animalia)
3. Protists (Protista)
4. Fungi
5. Eubacteria
6. Archaebacteria

3. Kingdom Plantae
Land plants include mosses, liverworts, hornworts, and vascular plants like trees and ferns
Obtain energy through photosynthesis

4. Kingdom Animalia Multicellular, eukaryotic , heterotrophic organisms
Water bears (Tardigrades) are eight-legged microscopic animals that are extremophiles
They can survive temp. of -273° C to over 151° C, 1,000 times more radiation than other animals, and live a decade without water. They have also lived over 10 days in the vacuum of space.

5. Kingdom Protista Protists are mostly unicellular, eukaryotic organisms
They include protozoa, ciliates, some molds and algaes.
Red algae is a multicellular example of a protist

6. Kingdom Fungi Fungi include mushrooms, molds, and yeasts.
Fungi are more related to animals than plants!
Eukaryotic decomposers
NA Destroying angel (Amanita bisporgia) death by liver hemorrhage within 2 days in most cases.
Most toxic mushroom in North America

7. Kingdom Eubacteria Single-celled, prokaryotic microorganisms
True bacteria
Biomass greater than all plants and animals on Earth
10x as many bacterial cells in human flora as there are cells in human body

8. Kingdom Archaebacteria
Single-celled organisms with no nucleus and no membrane-bound organelles
Extremophiles
Halophiles – extreme salt
Thermophiles – extreme heat

9. To organize all of these kingdoms, biologists use 3 domains.
Eukarya- protists, fungi, plants, and animals; uni- and multicellular, eukaryotes
Bacteria- eubacteria; unicellular prokaryotes, “true bacteria”
Archaea- archaebacteria; unicellular prokaryotes, no O2, extreme environments.

10. Exit Slip What are the three Domains of life?
2. Which Domains include only prokaryotic organisms? Which are only eukaryotic?