Classification

5.3 Classification of Biodiversity

Classification

• Classification involves arranging living organisms into groups based on similarities in structure, embryology, and DNA

What is the Value of Classifying Organisms?

• 1. Aiding the identification of species– When confronted with an unidentified species,

scientists look at classification keys which give hints to help provide a name for it.

• 2. Shows evolutionary links– Species in the same group usually share

characteristics since they have descended from a common ancestor. Classification can be used to predict how they evolved.

• 3. Predicting characteristics shared by similar species– If several species in a group share a

characteristic, another species in the group will probably share that characteristic.

What is a Species?

• A species is a group of organisms with similar characteristics, which can interbreed and produce fertile offspring. Their DNA will also be very similar.

Binomial System of Nomenclature:

• All identified species are given an international name, so scientists around the world can refer to it. The naming system that scientists use to name species is known as the binomial system since 2 names are used to refer to each species.

• Carolus Linneaus – Swedish Botanist that developed the classifying system.

• Binomial Nomenclature – 2 part scientific name.

• First word capitalized, not second• Written in Italics• Example: Homo sapiens

Example:

Genus Species Common Name

Homo sapiens Modern Humans

Homo erectus Java Man

Homo neanderthalensis Neanderthal Man

Three Domains of Classification

• Bacteria

• Archaea

• Eukaryota

Kingdoms of Life All life is classified into one of 5 kingdoms:

Kingdom Examples Characteristics

Prokaryotae Bacteria/ Blue-green Algae

Prokaryote cells: unicellular, no

nucleus, no organelles

Protoctista Protists/ Algae Eukaryote cells: unicellular & simple multicellular, nucleus,

organelles

Fungi Mold/ Yeast/ Mushrooms

Eukaryote: uni- to multicellular,

heterotrophs, mostly saprotrophs

Plantae Higher Plants Eukaryote: multicellular,

autotrophs, cellulose cell walls

Animalia Animals Eukaryote: multicellular,

heterotrophs, lack cell walls

Prokaryote

• 2. Protista – single cell eukaryotes. Has a Nucleus

• 3. Fungi – build cell walls. Heterotrophic. (do not make their own food)

• 4. Plantea (plants) – Autotrophic (make their own food). Includes Algae. Have cell walls.

• 5. Animalia – multi-cellular. No cell walls!

Seven Levels of Hierarchy of Taxa:

Hierarchy of Taxa Example #1 Example #2

Kingdom Animalia Plantae

Phylum Chordata Coniferophyta

Class Mammalia Pinopsida

Order Primate Pinales

Family Hominidae Pinaceae

Genus Homo Pinus

Species sapiens Pinus ponderosa (Ponderosa Pine)

1. Given the following scientific name: Felis rex

Which is the genus name?

• A) Felis

• B) rex

• C) Both are the genus name.

A) Felis (the first name of the scientific name is always the genus name. The genus name always begins with a capital letter!)

The use of the scientific name involving 2 names for each species is based on

which system?

• A) Monomial Nomenclature System

• B) Binomial Nomenclature System

• C) Trinomial Nomenclature System

• D) Polynomial Nomenclature System

B) Binomial Nomenclature System (bi=2, nomial = names)

Which kingdom do birds, mammals, fish, snakes and amphibians belong to? • A) Prokaryotae

• B) Protoctista

• C) Fungi

• D) Plantae

• E) Animalia

E) Animalia

Which kingdom do the bacteria and blue-green algae belong to?

• A) Prokaryotae

• B) Protoctista

• C) Fungi

• D) Plantae

• E) Animalia

A) Prokaryotae

Which kingdom do all mosses, ferns,

conifers and flowering plants belong to? • A) Prokaryotae

• B) Protoctista

• C) Fungi

• D) Plantae

• E) Animalia

D) Plantae

Which kingdom do the molds, yeasts and mushrooms belong to? • A) Prokaryotae

• B) Protoctista

• C) Fungi

• D) Plantae

• E) Animalia

C) Fungi

Why should organisms be classified?

• A) to make it easier to identify species

• B) to make predictions about similar species

• C) to make evolutionary links between similar species

• D) Answers A & B

• E) Answers A, B & C

E) Answers A, B & C

Which classification term below means a group of similar species?

• A) Genus

• B) Family

• C) Order

• D) Class

• E) Phylum

A) Genus

Which classification term below means a group of similar families?

• A) Genus

• B) Species

• C) Order

• D) Class

• E) Phylum

C) Order

Which of the following is the correct hierachary

of taxa from species to kingdom? A) Species : Phyla : Class : Order : Family : Genera :

KingdomB) Species : Genera : Order : Class : Family : Phyla :

KingdomC) Species : Genera : Family : Order : Class : Phyla :

KingdomD) Species : Family : Order : Class : Genera : Phyla :

KingdomE) Species : Genera : Aliens : Klingons : Romulans :

Vulcans : Kingdom

C) Species : Genera : Family : Order : Class : Phyla : Kingdom

Which of the following correctly describes

the classification of the organism at right?

A) Unicellular Consumer

B) Unicellular Producer

C) Multicellular Producer

D) Multicellular Consumer

D) Multicellular Consumer

Which of the following describes the

classification of the organism shown to the right?

A) Unicellular Consumer

B) Unicellular Producer

C) Multicellular Producer

D) Multicellular Consumer

C) Multicellular Producer

Which of the following is not a species?

A) Pinus ponderosa

B) Homo sapiens

C) Olsynium douglasii

D) Canis lupus

E) Mockingbird

E) Mockingbird