1. KEY CONCEPT The current Tree of Life has Three domains and Six Kingdoms.

2. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
From : Linnaeus created only two kingdoms, Animalia and Plantae
Animalia
Plantae

3. Classification is always a work in progress.
Until 1866: only two kingdoms, Animalia and Plantae
Plantae
Animalia
Protista
*1866: all single-celled organisms moved to kingdom Protista

4. Classification is always a work in progress.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Protista
Plantae
1866: all single-celled organisms moved to Kingdom Protista
Monera
*1938: prokaryotes moved to Kingdom Monera

5. Classification is always a work in progress.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Protista
Plantae
Animalia
1866: all single-celled organisms moved to Kingdom Protista
Fungi
1938: prokaryotes moved to Kingdom Monera
Monera
*1959: Fungi moved to own kingdom

6. Classification is always a work in progress.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Protista
Fungi
Plantae
1866: all single-celled organisms moved to Kingdom Protista
1938: prokaryotes moved to Kingdom Monera
Archea
Bacteria
1959: fungi moved to own kingdom
*1977: Kingdom Monera split into Kingdoms Bacteria and Archaea

7. The three domains in the tree of life are Bacteria, Archaea, and Eukarya.
Domains are above the kingdom level. (Larger category)
proposed by Carl Woese based on rRNA studies of prokaryotes
domain model more clearly shows prokaryotic diversity

8. Domain Bacteria includes prokaryotes in the Kingdom Bacteria.
one of largest groups on Earth
classified by shape, need for oxygen, and diseases caused ex. Strep, E. coli, staph infection, food poisoning

9. Domain Archaea includes prokaryotes in the
Kingdom Archaea. Ex. Halophiles , thermophiles
cell walls chemically different from bacteria -Peptidoglycan
differences discovered by studying RNA
known for living in extreme environments (hot, salty)

10. Domain Eukarya includes all eukaryotes.
1. Kingdom Protista (seaweed, diatoms, amoeba…)

11. Domain Eukarya includes all eukaryotes. 4 Kingdoms
2. Kingdom Plantae (mosses, ferns, conifers, flowering plants…)

12. Domain Eukarya includes all eukaryotes.
3. Kingdom Fungi (mushroom, athlete’s foot, mold, yeast…)

13. Domain Eukarya includes all eukaryotes.
Kingdom Animalia
(sponges, jellyfish,
roundworms, segmented
worms, flatworms,
echinoderms, mollusks,
arthropods, Chordates –
spinal cord such as
reptiles, fishes, mammals,
amphibians, birds)

14. Bacteria and archaea can be difficult to classify.
transfer genes among themselves outside of reproduction
blurs the line between “species”
more research needed to understand prokaryotes
bridge to transfer DNA

15. Figure 18-12 Key Characteristics of Kingdoms and Domain
Section 18-3
Figure Key Characteristics of Kingdoms and Domain
DOMAIN
KINGDOM
CELL TYPE
CELL STRUCTURES
NUMBER OF CELLS
MODE OF NUTRITION
EXAMPLES
Bacteria
Prokaryote
Cell walls with peptidoglycan
Unicellular
Autotroph or heterotroph
Streptococcus, Escherichia coli
Archaea
Archaebacteria
Prokaryote
Cell walls without peptidoglycan
Unicellular
Autotroph or heterotroph
Methanogens, halophiles
Protista
Eukaryote
Cell walls of cellulose in some; some have chloroplasts
Most unicellular; some colonial; some multicellular
Autotroph or heterotroph
Amoeba,
Paramecium, slime molds, giant kelp
Fungi
Eukaryote
Cell walls of chitin
Most multicellular; some unicellular
Heterotroph
Mushrooms, yeasts
Eukarya
Plantae
Eukaryote
Cell walls of cellulose; chloroplasts
Multicellular
Autotroph
Mosses, ferns, flowering plants
Animalia
Eukaryote
No cell walls or chloroplasts
Multicellular
Heterotroph
Sponges, worms, insects, fishes, mammals