Classify Organisms Qand A

1. ClassificationClassification
•Carolus Linnaeus, a Swedish naturalist, Carolus Linnaeus, a Swedish naturalist,
developed a new system of grouping developed a new system of grouping
organisms that was accepted and used by organisms that was accepted and used by
most scientists. most scientists.
•His classification system was based on His classification system was based on
looking for organisms with similar looking for organisms with similar
structures. structures.
•Linnaeus also developed a scientific Linnaeus also developed a scientific
naming system that is still used today. naming system that is still used today.

2. Binomial NomenclatureBinomial Nomenclature
•The two-word naming system that The two-word naming system that
Linnaeus used to name various Linnaeus used to name various
organisms is called organisms is called binomial binomial
nomenclaturenomenclature (bi NOH mee ul · NOH (bi NOH mee ul · NOH
mun klay chur). mun klay chur).
•This two-word name is an organism’s This two-word name is an organism’s
species.species.

3. Ambystoma
genus
Binomial NomenclatureBinomial Nomenclature
•The first word of the two-The first word of the two-
word name identifies the word name identifies the
genus of the organism.genus of the organism.
•A A genusgenus is a group of similar is a group of similar
species. species.
•The second word of the name The second word of the name
usually describes a feature. usually describes a feature.
tigrinum

feature

4. Uses of Scientific NamesUses of Scientific Names
•Scientific names are used for four Scientific names are used for four
reasons. reasons.
•First, they help avoid mistakes. First, they help avoid mistakes.
•Often, common names for two different Often, common names for two different
organisms are the same. organisms are the same.
•Scientific names help distinguish between Scientific names help distinguish between
those organisms. those organisms.

5. Uses of Scientific NamesUses of Scientific Names
•Second, organisms with similar Second, organisms with similar
evolutionary histories are classified evolutionary histories are classified
together. together.
•Third, scientific names give descriptive Third, scientific names give descriptive
information about the species. information about the species.
•Fourth, scientific names allow information Fourth, scientific names allow information
about organisms to be organized easily and about organisms to be organized easily and
efficiently.efficiently.

6. Uses of Scientific NamesUses of Scientific Names
•The classification of the bottle-nosed The classification of the bottle-nosed
dolphin shows that it is in the order dolphin shows that it is in the order
Cetacea. Cetacea.

7. Modern ClassificationModern Classification
•Like Linnaeus, modern scientists use Like Linnaeus, modern scientists use
similarities in structure to classify similarities in structure to classify
organismsorganisms.
•They also study fossils, hereditary They also study fossils, hereditary
information, and early stages of information, and early stages of
development. development.

8. Modern ClassificationModern Classification
•Phylogeny Phylogeny (fi LAH juh nee) is the (fi LAH juh nee) is the
evolutionary history of an organism, that evolutionary history of an organism, that
is, how the organism has changed over is, how the organism has changed over
time. time.
•Today, it is the basis for the classification Today, it is the basis for the classification
of many organisms. of many organisms.
•In the classification system used today, the In the classification system used today, the
smallest group is a smallest group is a speciesspecies..
•There are broader groups preceding There are broader groups preceding
species, the largest of which is a species, the largest of which is a kingdomkingdom..

9. Modern ClassificationModern Classification
•Some scientists have proposed that before Some scientists have proposed that before
organisms are grouped into kingdoms, organisms are grouped into kingdoms,
they should be placed in larger groups they should be placed in larger groups
called domains. called domains.
•One proposed system groups all One proposed system groups all
organisms into three domains. organisms into three domains.

10. Tools for Identifying OrganismsTools for Identifying Organisms
•Scientists use field guides and
dichotomous (di KAH tuh mus) keys to
identify organisms.
•A dichotomous key is a detailed list of
identifying characteristics that includes
scientific names.

11. MULTIPLE CHOICEMULTIPLE CHOICE
1. ___ PHYLOGENY TELLS1. ___ PHYLOGENY TELLS
A. How an organism is different from other A. How an organism is different from other
organisms.organisms.
B. How an organism has changed over time B. How an organism has changed over time
C. How an organism received its two part C. How an organism received its two part
scientific namescientific name
D. How Linnaeus started binomial D. How Linnaeus started binomial
nomenclature.nomenclature.
BB

12. MULTIPLE CHOICEMULTIPLE CHOICE
2. ___ The smallest group in the 2. ___ The smallest group in the
classification system used today is called aclassification system used today is called a
A. FamilyA. Family
B. GenusB. Genus
C. KingdomC. Kingdom
D. SpeciesD. SpeciesDD

13. MULTIPLE CHOICEMULTIPLE CHOICE
3. ___ Linnaeus developed a system of 3. ___ Linnaeus developed a system of
grouping organisms that was accepted by grouping organisms that was accepted by
most scientists. He grouped organisms with most scientists. He grouped organisms with
_______ together._______ together.
A. Dichotomous keysA. Dichotomous keys
B. Similar structures B. Similar structures
C. Similar fossilsC. Similar fossils
D. Similar hereditary informationD. Similar hereditary information
BB

14. MULTIPLE CHOICEMULTIPLE CHOICE
4. ___ Organisms that can mate and 4. ___ Organisms that can mate and
reproduce fertile offspring belong to the reproduce fertile offspring belong to the
same ______same ______
A. SpeciesA. Species
B. GenusB. Genus
C. KingdomC. Kingdom
D. DomainD. Domain
AA

15. SHORT ANSWERSHORT ANSWER
5. What is binomial nomenclature?5. What is binomial nomenclature?
AnswerAnswer
A two word naming system that Linnaeus A two word naming system that Linnaeus
used to name organisms and is now used in used to name organisms and is now used in
modern classificationmodern classification

16. 6. Explain three reasons scientific names 6. Explain three reasons scientific names
are usefulare useful AnswerAnswer
Any 3: 1) They help avoid mistakes and Any 3: 1) They help avoid mistakes and
confusion since each scientific name refers confusion since each scientific name refers
to only one kind of organism. 2) They help to only one kind of organism. 2) They help
show which organisms are related because show which organisms are related because
organisms with similar evolutionary organisms with similar evolutionary
histories are grouped together. 3) They give histories are grouped together. 3) They give
descriptive information about species. 4) descriptive information about species. 4)
They allow information about organisms to They allow information about organisms to
be organized easily and efficientlybe organized easily and efficiently