Transcript 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.
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?
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
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
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
• 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
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
• 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.