SIX KINGDOMS & SIX KINGDOMS & DOMAINSDOMAINSSection 9.1 cont….Section 9.1 cont….

The Kingdoms of LifeThe Kingdoms of Life

The Greek The Greek philosopher Aristotle, philosopher Aristotle, divided all living divided all living things into two large things into two large groups, known as groups, known as kingdomskingdoms: : Plantae Plantae & & AnimaliaAnimalia..

Along Came The Along Came The MicroscopeMicroscope

Classifying organisms became more Classifying organisms became more difficult after the microscope was difficult after the microscope was invented.invented.

The new tool revealed a previously The new tool revealed a previously unknown world of living things.unknown world of living things.

Some microscopic organisms have Some microscopic organisms have characteristics of both plants and characteristics of both plants and animals.animals.

ProtistaProtista

In 1866, the German In 1866, the German biologist Haeckel biologist Haeckel proposed classifying proposed classifying microorganisms that microorganisms that are neither animals are neither animals nor plants into a third nor plants into a third kingdom: kingdom: ProtistaProtista..

Fungi – The Fourth KingdomFungi – The Fourth Kingdom

As biologists learned As biologists learned more about the structure more about the structure and way of life of and way of life of different organisms, they different organisms, they added more kingdoms. added more kingdoms.

FungiFungi, originally in the , originally in the plant kingdom, do not plant kingdom, do not carry out photosynthesis. carry out photosynthesis. They obtain food by They obtain food by absorbing materials into absorbing materials into their bodies.their bodies.

EubacteriaEubacteria

Eubacteria consist of Eubacteria consist of very small cells that very small cells that differ in appearance differ in appearance from the cells of the from the cells of the other kingdoms. other kingdoms.

Bacteria lack a nucleus Bacteria lack a nucleus and other organelles.and other organelles.

They are classified in a They are classified in a fifth kingdom: fifth kingdom: EubacteriaEubacteria..

ArchaebacteriaArchaebacteria During the 1990s, there was During the 1990s, there was

growing interest in certain growing interest in certain types of bacteria found in types of bacteria found in extreme environments, such extreme environments, such as salt lakes or hot, acidic as salt lakes or hot, acidic springs.springs.

New studies found that New studies found that these bacteria were very these bacteria were very different from other bacteria.different from other bacteria.

The new data led scientists The new data led scientists to rename and reclassify to rename and reclassify these microorganisms into a these microorganisms into a sixth kingdom: sixth kingdom: ArchaebacteriaArchaebacteria..

Prokaryotes & Prokaryotes & EukaryotesEukaryotes

The study of cells is an important first step in The study of cells is an important first step in understanding the diversity of life.understanding the diversity of life.

Prokaryotic CellsProkaryotic Cells Eukaryotic CellsEukaryotic Cells

Eubacteria, archaebacteriaEubacteria, archaebacteria Protists, plants, fungi, animalsProtists, plants, fungi, animals

SmallSmall LargeLarge

DNA circular, not bounded by DNA circular, not bounded by membranemembrane

DNA in nucleus bounded by DNA in nucleus bounded by membranemembrane

Genome: 1 chromosomeGenome: 1 chromosome Genome: Many Genome: Many chromosomeschromosomes

Cell Division not by mitosis/meiosisCell Division not by mitosis/meiosis Cell Division: mitosis/meiosisCell Division: mitosis/meiosis

Asexual reproduction Asexual reproduction commoncommon

Sexual reproduction commonSexual reproduction common

Multicellular forms are rareMulticellular forms are rare Most are multicellularMost are multicellular

Mitochondria and other membrane-Mitochondria and other membrane-bound organelles are absentbound organelles are absent

Mitochondria and other organelles Mitochondria and other organelles presentpresent

Many are anaerobicMany are anaerobic Most are aerobicMost are aerobic

Fossil Evidence Fossil Evidence

The first forms of life were prokaryotic The first forms of life were prokaryotic organisms similar in appearance to bacteria.organisms similar in appearance to bacteria.

First prokaryotes appear: 3.5 billion years ago.First prokaryotes appear: 3.5 billion years ago. First eukaryotes appear: 1.5 billion years ago.First eukaryotes appear: 1.5 billion years ago. First multicellular organisms appear: 700 First multicellular organisms appear: 700

million years ago.million years ago.

The Three Domains The Three Domains Recent research on the cell has shown that Recent research on the cell has shown that

living prokaryotes are far more diverse than living prokaryotes are far more diverse than anyone had previously suspected.anyone had previously suspected.

This research led to a new level of This research led to a new level of classification above kingdoms, known as classification above kingdoms, known as domainsdomains..

The domain system better reflects the The domain system better reflects the evolutionary history of life.evolutionary history of life.

The three domains are: The three domains are: Eubacteria, Eubacteria, Archaebacteria and EukaryotaArchaebacteria and Eukaryota..

Domain Eukaryota Domain Eukaryota

Kingdoms: Protista, Fungi, Plantae and Kingdoms: Protista, Fungi, Plantae and Animalia.Animalia.

The greatest biological diversity occurs The greatest biological diversity occurs within the Kingdom Protista.within the Kingdom Protista.

For example, there is a much greater For example, there is a much greater genetic difference between some species genetic difference between some species of protists than there is between, for of protists than there is between, for example, corn and humans.example, corn and humans.

DomainDomain EubacteriaEubacteria Archae-Archae-bacteriabacteria EukaryotaEukaryota

KingdomKingdom EubacteriaEubacteria Archae-Archae-bacteriabacteria

ProtistaProtista FungiFungi PlantaePlantae AnimaliaAnimalia

# of Cells# of Cells UnicellularUnicellular UniUni MostlyMostly

uniuni

Mostly Mostly multimulti

MultiMulti MultiMulti

NucleusNucleus NoNo NoNo YesYes YesYes YesYes YesYes

Cell WallCell Wall YesYes SomeSome SomeSome YesYes YesYes NoNo

NutritionNutrition Autotroph Autotroph and and HeterotrophHeterotroph

Autotroph Autotroph and and HeterotrophHeterotroph

Autotroph Autotroph and and HeterotrophHeterotroph

HeterotrophHeterotroph AutotrophAutotroph HeterotrophHeterotroph

ReproductionReproduction AsexualAsexual AsexualAsexual Asexual Asexual and and SexualSexual

SexualSexual SexualSexual SexualSexual

Homework:Homework:

P. 334 #5,6P. 334 #5,6