Download Chapter 2

Chapter 2
Classification
Preview
Section 1 Sorting It All Out
Section 2 Domains and Kingdoms
Concept Mapping
Chapter 2
Section 1 Sorting It All Out
Objectives
• Explain why and how organisms are classified.
• List the eight levels of classification.
• Explain scientific names.
• Describe how dichotomous keys help in identifying
organisms.
Chapter 2
Section 1 Sorting It All Out
Why Classify?
The classification of living things makes it easier for
biologists to answer many important questions such as:
1. How many known species exist?
2. What are defining characteristics of each species?
3. What are the relationships between these species?
Chapter 2
Section 1 Sorting It All Out
How do Scientists Classify Organisms?
• Taxonomists currently use eight-level system to
classify living things based on shared
characteristics.
• On a branching diagram (cladogram), several
characteristics are listed along line that points to
the right.
• Each characteristic is shared by organisms
to the right of it.
Chapter 2
Section 1 Sorting It All Out
cladograms
Chapter 2
Section 1 Sorting It All Out
Eight Levels of Classification
1. Domain
2. Kingdom
3. Phylum
4. Class
5. Order
6. Family
7. Genus
8. Species
** Dumb King Philip came over for great spaghetti.
**Dumb kings play chess on fat green stools.
Chapter 2
Section 1 Sorting It All Out
Chapter 2
Scientific Names
One Species, One Name
A scientific name is
always the same for a
specific kind of organism
no matter how many
common names there
might be.
• EX: Puma concolor
mountain lion, cougar,
puma, panther,
painter
Chapter 2
What is the mental image you get
when the word “gopher” is said?
Chapter 2
Two-Part Names: binomial nomenclature
• first part of species name = genus Always capitalized.
• second part of name = species Never capitalized.
• Both words italicized if typed or underlined if
handwritten.
• EX:
Felis domesticus
Felis domesticus .
Chapter 2
Two-Part Names: binomial
nomenclature
Carolus Linnaeus (Carl von Linne)
Swedish scientist - developed modern
system of classification using two
scientific names
• Useful for scientists no matter what language
they speak to know exact organism to which
they refer
• EX: develop vaccine for specific disease
• Typically, names derived:
• from Latin or Greek (most often)
• in honour of discoverer
• famous scientist/person
• location of organism
Chapter 2
Section 1 Sorting It All Out
Dichotomous Keys
dichotomous key: a tool for identifying organisms
that uses a series of paired descriptive
statements.
By working through the statements in a
dichotomous key in order, a person can
eventually identify an unknown organism.
Chapter 2
Section 1 Sorting It All Out
Chapter 2
Dichotomous Key
class
activity
Chapter 2
Section 2 Domains and Kingdoms
Objectives
• Explain how classification developed as greater
numbers of organisms became known.
• Describe the three domains.
• Describe four kingdoms in the domain Eukarya.
Chapter 2
A Growing System
• People are still discovering and classifying organisms
(especially in the ocean).
• Sometimes new organisms are found that are so different
from other known organisms that new classes, phyla, etc.
must be formed.
• EX:
• 50 years ago, only 2 kingdoms used: Plants, Animals
• As technology improves, organisms may need to be
reclassified (DNA sequencing, cellular chemistry, etc)
Chapter 2
Section 2 Domains and Kingdoms
• What Is Used to Classify Organisms? Organisms
classified by their characteristics.
• Adding New Classification Categories As scientists
continue to learn about living things, they add
classification categories that account for characteristics
of different organisms.
• Classification systems will vary by age of publication.
Those older than 10 years typically do not include the
domains.
Chapter 2
THREE DOMAINS:
1. Archaea (Archaebacteria)
2. Bacteria (Eubacteria)
3. Eukarya (Eukaryota)
Chapter 2
Chapter 2
The 6 Kingdoms
Chapter 2
Section 2 Domains and Kingdoms
The Two Kingdoms of Bacteria
• Domain Archaea:
• one of two kinds of prokaryotes
• Prokaryotes: single-celled organisms that do
not have a membrane-bound nucleus and
organelles.
• most live in extreme environments:
• hot springs (thermophiles)
• high salt or sulfur (halophiles)
• high pressure in deep ocean or underground
• frigid areas
Chapter 2
The Two Kingdoms of Bacteria
• Domain Eubacteria:
• prokaryotes
• can be found nearly everywhere on Earth:
• soil (nitrogen-fixers, decomposers)
• water
• on/inside human body (EX: E. coli)
• Most bacteria are harmless to humans, acting as
decomposers, nitrogen-fixers, etc.
Chapter 2
Section 2 Domains and Kingdoms
The Domain Eukarya
• eukaryote: has membrane-bound nucleus
and organelles
Kingdom Protista
• commonly called protists
• single-celled or simple multi-cellular organisms
• Any organism NOT classified as plant, animal, or
fungi is placed here: “garbage can” kingdom
Chapter 2
Kingdom Protista
• Protists classified as:
– Plant-like – contain chlorophyll (algae)
– Animal-like – move using cilia or flagella,
predatory (protozoans and euglenoids)
– Fungus-like – absorb/engulf decaying organic
matter similar to fungi (slime molds)
Chapter 2
Paramecium >
Common
Protists
Amoeba
Euglena
Chapter 2
and an uncommon one….
dog vomit slime mold
Chapter 2
Section 2 Domains and Kingdoms
The Domain Eukarya, continued
• Kingdom Fungi
• complex, multi-cellular eukaryotes
• molds
• mushrooms
• yeasts
• Heterotrophic: do not make own food
• Do not perform photosynthesis nor “eat” food.
• Instead, absorb nutrients from substances in
their surroundings, esp dead organic matter
• Analogy: spit on food, digestive juices
break down it down, absorb the nutrients
thru skin
Chapter 2
Kingdom
Fungi
Chapter 2
Section 2 Domains and Kingdoms
Kingdom Plantae
• Plants
• complex, multi-cellular organisms
• eukaryotic
• have cell walls
• autotrophic (make own food through photosynthesis
 require sunlight)
• Examples of Plantae mosses, trees, flowers, grasses,
ferns, and more.
Chapter 2
Kingdom Plantae
Chapter 2
Section 2 Domains and Kingdoms
Kingdom Animalia
• Animals
• heterotrophic
• complex, multi-cellular organisms
• do NOT have cell walls
• able to move around at some point in lifetime
• have specialized sense organs
• Examples of Animalia Ants, beetles, lizards, fish,
birds, humans, elephants, and more.
Chapter 2
Kingdom Animalia