Download Ecosystem

Environmental Science
Chapter 4:
The Organization of Life
The Organization of Life Big Ideas
In an ecosystem, the biotic and
abiotic components interact to form
an interconnected system.
 Species adapt to their environment
through the process of evolution by
natural selection.
 Humans classify the diversity of life
on Earth in order to better
understand their relationships.

Section 1: Ecosystems
GOALS
 Distinguish between biotic and abiotic
factors in an ecosystem
 Describe how a population differs from a
species
 Explain the importance of habitats
What is
Ecology?
The study of
interactions among
organisms and
between organisms
and their
environment.
What is an ecosystem?
Defining an ecosystem
Ecosystem: all the
organisms living in an
area together with
their physical
environment
 Forest Ecosystem
 Pond Ecosystem
 Vacant Lot Ecosystem
 Desert Ecosystem

All Ecosystems are connected
How does your
ecosystem
impact the
Atlantic Ocean?
Parts of an ecosystem
Parts of an ecosystem
In order for an ecosystem
to survive it needs five
basic components:
 Energy
 Mineral Nutrients
 Water
 Oxygen
 Living Organisms
What are some parts of this
ecosystem?
If your are conducting a study
of the interactions of
vegetation, animals, mineral
composition of the soil, and
water levels in a saltmarsh. You
are studying the saltmarsh ___.
ECOSYSTEM
Biotic and Abiotic Factors
Biotic: living & once
living parts of an
ecosystem
 Plants, animals,
bacteria, dead
organisms, wastes
Abiotic: nonliving parts
of an ecosystem
 Air, water, soil,
sunlight, temperature
What are some biotic AND abiotic parts of this ecosystem?
Pair and Share Activity:
With a partner of your
choice, create a table that
lists the abiotic and biotic
things in this classroom.
Abiotic
Biotic
Organizing Biotic
Parts
Smallest Unit
Organism: an individual
living thing like you, a
tree, a fox, a rose
Species: groups of
closely related
organisms that can
mate & produce fertile
offspring like red foxes
or black widow spiders,
or grizzly bears
Species
Species: groups of
organisms that
resemble each other
in appearance,
behavior, chemistry
and genetic
makeup…able to
reproduce
 3.6 to 100 million
species (1.4 identified)
 Mostly insects/micro
 Tropical forests
Insects
751,000
Known
species
1,412,000
Plants
248,400
Population
Population: all the
members of the same
species that live in the
same place at the same
time
– Field mice living in a corn
field, grizzly bears of
Yellowstone Park
– Members breed with one
another, rather than with
other populations
Community
Community: a group of
various species that
live in the same place
and interact with
each other
–Pond Community
–Pineland Forest
Community
Giraffes, lions, zebras, hyenas,
and all the other living things of
the Serengeti make up a(n) ___
COMMUNITY
Habitat
Habitat: the place
where an organism
lives
– Organisms are well
suited for their
habitat
Habitat
 Habitats
provide an
organism with
resources—
anything an
organism needs to
survive and
reproduce,
including food,
shelter, and mates
Biosphere
 All
parts of the
Earth where
life is found
Section 1 Review
Biotic are living factors in an ecosystem
 Abiotic are non-living factors in an
ecosystem
 Biosphere is composed of ecosystems,
ecosystems are composed of communities,
community is made up of populations,
populations are composed of species, species
are composed of individuals
 Habitats provide organisms with the
resources they need to survive

Section 2: Evolution
GOALS
 Explain the process of evolution by natural
selection
 Explain the concept of adaptation
 Describe the process of resistance
How have you
changed (not just
physically) since you
were a child?
Change is one thing
that is certain in
life.
Change occurs in
many ways
-cultures change
-individuals change
-species change
Essential
Question:
You’ve read about the
diversity of living organisms
on Earth (plants, animals,
protists, fungi, bacteria)
How did they get
here?
What is
Evolution?
Change in the
genetic
characteristics
of a population
over time!
- biologists say that the
environment exerts a strong
influence over which individuals
survive to produce offspring
- the best suited (most fit)
organisms survive and reproduce
- individuals with certain traits
are more likely to survive and
reproduce
Natural Selection
aka
“Survival of the Fittest”
- the unequal survival and
reproduction that results from
the presence or absence of
particular traits
Evolution by Natural Selection
1-Organisms produce more offspring than can survive
2-The environment is hostile and contains limited resources
3-Organisms differ in the traits they have
4-Some inherited traits provide organisms with an advantage
(ADAPTATION)
5-Each generation contains proportionately more organisms
with advantageous traits
Natural
Selection
Hammer Orchid
Coevolution
Process of 2 species evolving in response to long term
interactions with each other
Question:
If natural selection concludes that all dogs are closely
related through a common ancestor, then how come this
Chihuahua and this Great Dane are so different?
Artificial Selection:
Artificial selection refers to the process where
humans select organisms with certain traits to
breed.
Resistance:
Resistance occurs when humans expose organisms
to certain conditions/chemicals, and those
organisms become tolerant or “immune” to the
conditions over time.
Examples:
A. Insects can become resistant to pesticides
B. Bacteria can become resistance to antibiotics
Section 2 Review
Evolution by natural selection is the
unequal survival and reproduction that
results from the presence or absence of
particular traits
 Adaptation increase an organism’s chance
of survival and reproduction in a certain
environment
 Resistance is the ability of an organism to
tolerate a particular chemical or condition
designed to kill it

Question: What is your favorite
organism(s) of all time? Why?
This cat’s favorite organism is a frog.
Section 3: The Diversity of Living
Things
GOALS

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Name the five kingdoms of organization and
identify characteristics of each
Explain why bacteria and fungi are important
Describe the importance of protists in the ocean
environment
Describe the interdependence of angiosperms
and animals
Explain why insect animals are so successful
Bacteria:
-single-cell, no nucleus
-cell wall
-reproduce by division
-two types
•Archaebacteria (extremophiles)
•Eubacteria
-most diverse & common
organisms on Earth
-many important roles
• decomposers, recyclers, assist
in digestion
Examples?
- E. coli, cyanobacteria
Video: Bacteria - The Good and
The Bad
Video: How Bacteria Talk
Airborne Bacteria Lab
-Bacteria are so important, that
humans (and many other organisms)
would be extinct without them.
-The point of this lab is to review
the scientific method, and gain an
appreciation for how much bacteria
we are surrounds by.
Fungi:
-single cell, nucleus, cell
wall, no chlorophyll
-absorb food from around
them
-decomposers: feed on
dead organisms
-Examples?
(Athlete’s foot, cheese, yeast)
Protists:
-many single-celled
-very diverse, most live in
water
-important role
(algae/phytoplankton)?
Examples?
Diatoms, dinoflagellates, amoeba,
paramecium, amoeba, kelp
Plants:
-many cells, cell wall
-photosynthesize
-most land dwellers
-supply oxygen and food to
much of the world
-gymnosperms (conifers)
-woody plants
-seeds not enclosed in fruits
-angiosperms (flowers/fruits)
-flowering plants
-produce seeds in fruit
-important role?
Most land animals depend on flowering plants
for food
Animals:
-many cells
-no cell wall
-must take in
food
-live on land or
water
Animal Types:
-Invertebrates
-no backbone
-Vertebrates
-have backbone
Insect Success:
-waterproof external
skeleton
-move quickly
-reproduce quickly
-most can fly
-small size
-little food needed
-hide
-insects & plants coevolved
-pollination
-eat plant pests
Section 3: Review
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The five kingdoms are bacteria, fungi, protists,
plants, animals
Bacteria and fungi are decomposers, recyclers
and help release nutrients
Protists in the ocean are the primary source of
food
Most animals rely on angiosperms for food
Insect animals are so successful because of their
exoskeleton, size, agility, capacity to fly and hide
The Organization of Life Big Ideas
In an ecosystem, the biotic and
abiotic components interact to form
an interconnected system.
 Species adapt to their environment
through the process of evolution by
natural selection.
 Humans classify the diversity of life
on Earth in order to better
understand their relationships.
