Interdependence of Life
(Classifying Life & )
S7L.1
S7L.4
S7L.1 Students will investigate the diversity of living
organisms and how they can be compared scientifically.
a. Demonstrate the process of the development
of a dichotomous key.
b. Classify organisms based on physical
characteristics using a dichotomous key of the
six kingdom system (archaebacterial, eubacteria,
protists, fungi, plants, and animals).
Vocabulary
organism
Homeostasis
Dichotomous key
Response stimulus
Classification
Plantae
Phylogeny
Animalia
Vocabulary
Taxonomy
Archaebacteria (bacteria)
Binomial nomenclature
Eubacteria (bacteria)
Fungii
Protista
Prokaryote
Eukaryote
Vocabulary
•
•
•
•
•
•
•
Autotroph (producer)
Heterotroph (consumer)
Cell
Kingdom
Scientific Name (genus & species)
Multicellular
Unicelluular
What is a living thing?
How are living things, or organisms
alike?
1. Living things are organized.
a. Cell – the smallest unit of an organism
that carries on the functions of life.
b. Each cell has an orderly structure and
contains hereditary material.
How are living things, or organisms
alike?
2. Living things respond.
a. Stimulus – that causes some change in
an organism.
b. Response – the way an organism reacts
to a stimulus, often results in
movement.
c. Homeostasis – maintaining the proper
conditions inside an organism.
How are living things, or organisms
alike?
3. Living things grow and develop.
a. Growth of multi-cellular organisms is
due to an increase in the number of
cells.
b. Growth of uni-cellular organisms is due
to an increase in the size of the cell.
c. Development – changes that take place
during the life of an organism.
How are living things, or organisms
alike?
4. Living things use energy.
5. Living things reproduce.
What do living things need?
1. A place to live that provides for all of the
organism’s needs.
2. Raw materials like water, proteins, and
sugars.
Question
What do you have in common
with a flower?
• Both are organized & have
cells.
• Both respond to stimuli &
maintain homeostasis
• Both take in & use energy:
plant (sun), human (food)
• Both grow, develop, &
reproduce
• Both need a place to live &
raw materials.
• Both contain organic
compounds.
Where does life come from?
A. Spontaneous generation – early theory that
living things could come from nonliving
things.
(Disproved by Louis Pasteur in the mid-1800’s)
B. Biogenesis – theory that living things come
from other living things.
Classification of Living Things
How are living things classified?
A. Classification systems:
1. Aristotle classified organisms more than
2,000 years ago.
2. Carolus Linnaeus introduced a system
based on similar structures of organisms.
3. Modern systems based on phylogeny –
the evolutionary history of an organism.
How are living things classified?
4. Today’s classification system separates
organisms into 6 kingdoms.
a. Kingdoms are the first and largest
category.
b. the smallest classification category
is a species.
c. Organisms that belong to the same
species can mate and produce
fertile offspring.
How are living things classified?
B. Binomial nomenclature – two word system
used by Linnaeus to name species .
1. First word identifies the genus, or group
of similar species.
2. Second word tells something about the
species – what it looks like, where it is
found, or who discovered it.
How are living things classified?
3. Why use scientific names?
a. To avoid mistakes
b. to show that organisms in the
same genus are related
c. To give descriptive information
d. to allow information to be
organized easily.
How are living things classified?
C. Tools for identifying organisms
1. Dichotomous keys – detailed lists of
identifying characteristics that include
scientific names.
Classifying Living Things
Levels of Classification
Level of Classification
Human Example
Dog Example
Kingdom
Animals
Animals
Phylum
Chordates
Chordates
Class
Mammals
Mammals
Order
Carnivores
Carnivores
Family
Canidae
Genus
Homo
Canis
Species
sapiens
lupus
Kingdoms
Kingdom
Trait
Examples
Archeabacteria
Uni-cellular, Prokaryotic,
some move & others do not,
heterotroph & autotrophs,
found in extreme
environments
Bettle, duck, earthworm,
salmon, horse, human
Eubacteria
True bacteria, uni-cellular,
prokaryotic, some move &
others do not, heterotroph &
autotroph, live anywhere
Stretococcus, staphylococcus,
e-coli, L. acidophiolus
Fungi
Multicellular, Eukaryotic,
Decomposers,
Bread
Protists
Most are uni-celled,
Eukaryotic, some move,
others do not, heterotroph &
autotroph
Algae, amoeba, giant kelp,
paramecium, slime mold
Plantae
Multi-cellular, Eukaryotic,
cannot move, autotrophs
Corn, moss, redwood tree,
rose
Animalia
Multi-cellular, Eukaryotic,
Mobile, Heterotrops
Beetle, duck, earthworm,
salmon, horse, human
Kingdom Traits
Trait
Meaning
Example
Uni-cellular
One cell
Multi-cellular
Many cells
Animals
Heterotroph
Consumer – eats other
organisms
Animals
Autotroph
Producer – makes its own
food (photosynthesis)
Plants
Decomposer – eats dead
organisms
Fungi
Eukaryotic
Has a nucleus and
organelles
Animals, plants, fungi,
protist
Prokaryotic
Does not have a nucleus or
organelles
Eubacteria, archaebacterial
Asexual
How it reproduces
Binary, fission,
regeneration
Dichotomous Key
Question
How do scientific names
show you that organisms
are related?
Organisms with similar
evolutionary histories
(phylogeny) are classified
together. Because of this,
you know that organisms
in the same genus are
related.
Big Ideas
• Organisms are classified into six kingdoms.
• Differences and similarities exist within the structures
and functions among the six kingdoms.
• Kingdoms are based on:
– Cellular structure (uni-cellular, multicellular)
– Method of obtaining food for energy (autotroph,
heterotroph, decomposer)
– Cellular structure (prokaryotic, eukaryotic)
– The diversity of living things created the need for a
dichotomous key.
– Dichotomous keys are made of paired and opposite
statements that allow the reader to identify organisms.
Essential Questions
•
•
•
•
•
•
•
•
How do you use a dichotomous key?
Why is a dichotomous key useful?
Where does the energy in my food come from?
Why should the health and well-being of other
organisms be important to me?
Why are there fewer animal than plants?
Why are there so many different kinds of
organisms?
How are we related?
Where did all that energy come from?
S7L.4 Students will examine the dependence of
organisms on one another and their environments.
a. Demonstrate in a food web that matter is transferred from
one organism to another and can recycle between organisms
and their environments.
b. Explain in a food web that sunlight is the source of energy
and that this energy moves from organism to organism.
c. Recognize that changes in environmental conditions can
affect the survival of both individuals and entire species.
d. Categorize relationships between organisms that are
competitive or mutually beneficial.
e. Describe the characteristics of the Earth’s major terestrial
biomes (i.e. tropical rain forest, savannah, temperate, desert,
taiga, tundra, and mountain) and aquatic communities (ie.
Freshwater, estuuaries, and marine)