Ecology Notes(1)

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Ecology
Interactions Between Organisms and
their Environments
Mr. Broderick
NC SCOS Goal 5
Lesson #1: Living and non-living parts
of an Ecosystem
• Objectives
– Identify abiotic and biotic factors in a given
description of an ecosystem interaction
– Generate an example relationship using abiotic
and biotic factors
– Determine if a solution is acidic, basic, or neutral
given its pH
– Set-up an experiment to test the effect of pH on
the sprouting of a lima bean
• Develop hypothesis, procedure
Key Vocabulary to Define
•
•
•
•
•
•
•
Ecosystem
Abiotic
Biotic
pH
Acidic
Basic
Neutral
The organization of our world!
The earth is a biosphere
Ecosystems are the
living and nonliving
things in an area
Populations are a group
of one type of organism
living in an area
Hierarchy of Biology
• Ecosystems
• Communities
• Populations
• Organisms
• Organ systems
• Organs
• Tissues
• Cells
• Organelles
• Molecules
What is ecology?
• Ecology: The study of the relationship between
organisms and their environment
• Example problems that ecology handles:
– How do humans affect the atmosphere and
contribute to global warming?
– How does the population of wolves in an area
affect the population of rabbits?
– Do clownfish (Nemo!) and anemone benefit each
other?
Why does ecology matter?
• Ecology: The study of the relationship between
organisms and their environment
Scenario: Imagine that there is an insect that lives
on peanut plants growing on farms in
Northampton County. Is there a way that we can
limit insect damage to the peanut crops in order
to decrease the price of peanuts at the store by
20 cents per pound?
How do we study environments?
• Quadrant Studies: Tracking changes in a small
section of the environment
How do we study environments?
• Sampling: Only measuring a small, random part
of an environment
Ecosystems
• Ecosystem: An area containing an interaction of
living and non-living factors in an area/region
• Example ecosystems:
– North Carolina forests (pine forests)
– Coastal Plains of NC
– Outer banks coastal water ecosystem
– Lake Gaston ecosystem
What is in an Ecosystem?
• Abiotic Factors: The non-living parts of an
ecosystem
– Rocks, soil, temperature, gases in the air, light
• Biotic Factors: The living parts of an ecosystem
– Plants, animals, bacteria, fungus
• Producers: use light to make their own energy
• Consumers: eat other organisms to obtain energy
• Decomposers: break down dead organisms for energy
Word Parts!
• Placing an “a” before a word makes it an
opposite or not
– Abiotic (not biotic; not living)
– Atypical (not typical)
– Anonymous (no name)
Biotic
Abiotic
•
•
•
•
•
•
•
•
•
•
•
•
•
Humans
Bacteria
Fungus
Plants
Insects
Amphibians
Reptiles
Mammals
Birds
Water
Soil
Wind or Air
Gases
– oxygen, carbon dioxide,
nitrogen
• Temperature
• Sunlight
• pH
– Acid or base
Abiotic or Biotic?
Biotic
(plant)
Abiotic
(rainwater)
Abiotic or Biotic?
•
•
•
•
•
The air temperature is 45 degrees F = abiotic
The soil is made of rocks and minerals = abiotic
A bird lays eggs = biotic
Bacteria break down dead organisms = biotic
The pH or the water is 2 (acidic) = abiotic
Abiotic or Biotic?
Biotic
Abiotic
Biotic
Biotic
Which of the following is a relationship
between abiotic and biotic factors?
A) The rain on an open field washes away soil
B) A hawk hunts a mouse and swoops down into
the forest for the kill
C) A lake has very acidic water which causes
many fish populations to die
Abiotic
D) A deer grazes in a field of grasses
Biotic
Independent Work
• Read your scenario card
• Identify the abiotic and biotic factors in the
scenario
• Now, find others with your letter and check
your work.
Mini-Lesson: pH
• pH: the measurement of how acidic, basic, or
neutral a solution is
Weakly Acidic
Weakly Basic
1 ------------ 4 ----------- 7 ------------ 11 ------------- 14
Neutral
Strong Base
Strong Acid
(very basic)
(very acidic)
Guided Examples
• Vinegar
– pH of 4
Acidic
• Baking Soda Basic
– pH of 8-9
• Tap water
– pH of about 7
Neutral
• 1 M HCl (hydrochloric acid)
– pH of about 1
• 1M NaOH
– pH of about 14
Basic
Acidic
Guided Examples
• Which is more acidic?
A)
B)
C)
D)
pH of 2
pH of 5
pH of 7
pH of 11
• Which is more basic?
A)
B)
C)
D)
pH of 2
pH of 5
pH of 7
pH of 11
A scientist performs an experiment to see if acids have an effect
on the health of a particular type of plant. Three sets of plants
were treated with acidic solutions of known pH while the control
set was treated with a solution of neutral pH 7.
What is the best conclusion for this experiment?
A. Acid has no effect on
the health of this type
of plant
B. High acidity is helpful to
this type of plant
C. Low acidity is harmful to
this type of plant
D. High acidity is harmful
to this type of plant
Energy Transfer in an Ecosystem
NCSCOS 5.02b
Food Chains
• A food chain shows the flow of energy between
the organisms in an environment
Food Chains
• Notice that the arrow points from the organism
being eaten to the organism that eats it.
– Like the burger you eat goes into you
Plants  Cow (burger)  Human
What do the arrows in the food chain
below indicate?
A.
B.
C.
D.
Sunlight
Energy flow
Heat transfer
Toxins
What is energy?
• The energy that is transferred in an ecosystem
is stored in carbon-compounds, or organic
compounds.
– Organic compounds: molecules that contain a
carbon atom
• Carbohydrates: glucose, starch, cellulose (mostly plants)
• Proteins: the muscles of animals (steak!)
• Fats: in muscle of animal tissues (fatty steak!)
Food Webs
• When we put many food chains together in
one ecosystem, it is called a food web
Food Webs
• Food webs show the direction that energy
flows in an ecosystem.
Energy Moves in a Food Web
Other animals get
energy from the fat
and protein in
other animals
Some animals
get glucose
from plants
Plants make
glucose
from light
Parts of a Food Web
• Producers: organisms that use light to store
energy in organic compounds.
– (examples: plants, algae, phytoplankton)
Parts of a Food Web
• Where are the producers in the food web
below?
Parts of a Food Web
• Consumers: organisms that eat other
organisms to get organic compounds that they
use for energy
– (examples: humans, cows, insects, birds…)
Parts of a Food Web
• Where are the consumers in the food web
below?
Parts of a Food Web
• Tertiary consumers: organisms that eat
secondary consumers for energy
• Secondary consumers: organisms that eat
primary consumers for energy
• Primary consumers: organisms that eat
producers to obtain energy compounds
Tertiary Consumer
Secondary Consumer
Primary Consumer
Producer
How is energy stored and transferred
in an ecosystem?
A.
B.
C.
D.
In light
In oxygen and carbon dioxide
In carbon compounds like glucose
In the process of decomposition
Which of the following organisms is a
primary consumer in the ecosystem
shown?
A.
B.
C.
D.
Hawk
Rabbit
Mountain lion
Frog
Population Impacts in a Food Web
• If the population of organisms at any level of
the food web changes, it will affect the
population at other levels
Population Impacts in a Food Web
• If the population of producers decreases, then
the population of primary consumers will
decrease if they don’t have enough food.
Population Impacts in a Food Web
• If the population of primary consumers
decreases, then…
– The producers will increase because there are less
consumers eating them
– The secondary consumers will decrease because
there is less food for them
Which organism would be most affected
if the cricket population decreased?
A.
B.
C.
D.
Snake
Deer
Frog
Hawk
Energy Pyramids
• Energy Pyramids show the amount of energy
at each level of a food web
– Trophic Level: the total amount of energy in all
organisms at one level in the food web.
Energy Pyramids
• More energy at
the bottom,
decreases as the
pyramid moves
up the food web
Less Energy
More Energy
Energy Pyramid Labels
Tertiary
Consumers
Secondary
Consumers
Primary
Consumers
Producers
Energy Transfer in Energy Pyramids
• Each trophic level of the energy pyramid
supplies energy to the level above it.
• Each transfer loses 90% of the energy
• Only 10% of the energy at a level is passed to
the next level up!
Energy Transfer (percents)
0.1%
1%
10%
100%
Energy Transfer (calories)
1 calorie
10 calories
100 calories
1,000
calories
Energy Transfer in Energy Pyramids
• We can say that the energy transfer from level
to level is inefficient
– (not a lot of the energy at each level makes it up)
• This means that there can’t be many levels ina
food web or pyramid
– The amount of energy decreases, and it cannot
typically support organisms at higher levels than
tertiary consumer
Why are there a limited number of
energy levels in an energy pyramid or
food web?
A.
B.
C.
D.
Energy transfer is very efficient
Energy is captured as heat
Energy transfer is inefficient
Energy is not transferred in a food web
Energy Transfer and Flow
NCSCOS 5.02a, 2.05bc
How does energy enter the food web?
Better question… where does the
weight of a producer come from?
How does this...
become this?
Photosynthesis
• Photosynthesis: a toxin process that occurs in
producers and converts light, carbon dioxide,
and water into glucose (sugar) and oxygen.
Carbon
Dioxide
Water
Sunlight
Glucose
Oxygen
More Photosynthesis
a. Photosynthesis removes carbon dioxide
from the air.
b. The carbon dioxide in the air is the
building block for glucose.
c. The light energy helps bond CO2 and H2O
together to make glucose.
• The energy in light is now stored in the
glucose molecule
Starch
Fat
(nuts)
Glucose
Light
CO2
O2
H2O
How do consumers get energy?
• Digestion of organic molecules
– Consumers eat other organisms to obtain organic
molecules, which are forms of stored energy.
– Energy is stored in the bonds of the molecules.
The Carbon Cycle
NCSCOS 5.02a
Carbon Cycle
• Carbon is found throughout the environment
– Carbon is found in the atmosphere and in water as
carbon dioxide (CO2)
– Carbon is found in organisms as organic
molecules, like glucose (sugars) and fats
– Carbon is found buried in the ground as fossil fuels
Carbon Cycle
• Carbon is cycled, or moves
1) Atmosphere: Carbon is in the form of CO2
CO2
Carbon Cycle
2) Producers: Use photosynthesis to make sugars
from CO2 in the atmosphere (carbon is moved!)
C6H12O6
Carbon Cycle
3) Consumers: Eat organic molecules and release
CO2 into the atmosphere during respiration, or
die and go into the soil
CO2
Carbon Cycle
4) Soil: decomposers break down organisms,
releasing carbon into the atmosphere OR
trapping it in the ground (fossils)
Carbon Cycle
5) Fossil Fuels: carbon from some dead organisms
are trapped as fossil fuel until we burn it
Carbon Cycle Stations
• Start at one of the stations
• Make your way to each different station based
on a correct path through the carbon cycle
• If you can go to two different places, choose
between them and then go back
• Write all answers on your sheet!
• After you are done, explain to your partner
the “story” of the carbon cycle, and have
them explain back to you!
Greenhouse Effect and Global Warming
Greenhouse Effect
• Heat is trapped near the Earth’s surface
because once light gets in, it warms the
surface but cannot escape out of the
atmosphere.
– It is trapped by the gases in the atmosphere, like
CO2
Global Warming
Global Warming
• The Earth has been warming on average.
• Could be due to increased CO2 emissions into
the atmosphere, which enhances the
greenhouse effect and traps extra heat.
Global Warming
Excess CO2  Enhanced  Global Warming
Greenhouse
Effect
Relationships in an Ecosystem
NCSCOS 5.01
Symbiosis
• Symbiosis: a long-term relationship between
two organisms in an ecosystem.
Types of Symbiosis
• Mutualism: both organisms benefit from their
relationship
• Commensalism: one organism benefits, and
the other is unaffected
• Parasitism: one organisms benefits, and the
other is harmed
Symbiosis Summary
Relationship
Type
Species A
Species B
Mutualism
+
+
Commensalism
+
0
Parasitism
+
-
Name That Symbiosis
• Leeches feed off of the lamprey below, and
eventually cause it to die.
Name That Symbiosis
• A clown fish lives among the sea anemone.
The clown fish gains protection, but the
anemone is neither harmed nor helped.
Name That Symbiosis
• Ox-peckers live on the heads of the ox, eating
insects and keeping the ox clean. The birds
also get a place to live.
Example: The Malaria Parasite
• Species: Plasmodium Vivax
• Organism: Protist
• Disease: Malaria, which is prevalent in Africa
A. Plasmodium Vivax is a one-celled organism
that is transmitted to humans through the
bite of the female Anopheles mosquito
B. It enters liver cells and begins to reproduce
C. The reproductive cells infect blood cells.
D. Which causes them to lyse or burst.
E. The reproductive cells can be picked up by
another mosquito, where they reproduce
(G) and are transmitted to another human
(H)
Population Growth and
Overpopulation
NCSCOS 5.03
Populations
• Population: the number of organism from one
species that live in a specific area
– Examples: the human population in different cities,
the squirrel population in a forest, the grass
population in a meadow
Populations
• Populations are affected by many resources.
These include:
–
–
–
–
–
The amount of food available in an area
The amount of sunlight (if it is a plant population)
The amount of water
The competition for food/shelter
The predators in an area
Population Growth Graphs
Birth Rate > Death Rate
A: Slow growth as a population begins to grow
Population Growth Graphs
Birth Rate > Death Rate
B: Exponential growth as population grows rapidly
Population Growth Graphs
Birth Rate > Death Rate
C: Slow-down of growth as population maxes out
its resources, like food, water, or light
Population Growth Graphs
Birth Rate = Death Rate
D: Population reaches the maximum number
supported by environment, the carrying capacity
Carrying Capacity
• Carrying Capacity: the maximum number of
organisms in a population that are supported by the
environment
Population Growth Graphs
Reaching Limit
of Resources
Exponential
Growth, no
limiting
resources
Carrying Capacity
Carrying Capacity
• Populations are typically limited by resources
– They reach carrying capacity when there aren't
enough resources to keep growing.
– Birth Rate = Death Rate.
– Logistic Growth!
Unlimited Growth
• If there are no limiting resources, populations
grow exponentially.
• Birth Rate > Death Rate
Decline
• If population birth rate < death rate, the
population will go down!
Which of the following graphs shows a
population that is free of limiting factors?
Which of the following graphs shows a
population that has reached carrying capacity?
How would a scientists determine the
growth rate of a population?
A.
B.
C.
D.
Birth Rate + Death Rate
Birth Rate – Death Rate
Birth Rate x Death Rate
Birth Rate / Death Rate
Click To Go Back and Analyze The Graphs
In Terms of Birth And Death Rates (with the class)
What statement best describes the population
shown in the graph below?
A. Birth rate = Death rate
B. Birth rate < Death rate
C. Birth rate > Death rate
D. Birth rate = 0
What statement best describes the population
shown in the graph below at time “t”?
A. Birth rate = Death rate
B. Birth rate < Death rate
C. Birth rate > Death rate
D. Birth rate = 0
Predator vs Prey
• Predator and Prey populations can affect one
another
1. As prey increases, predator will increase in
response
2. As predators increase, prey will decrease
3. As prey decrease, predators will decrease
POPULATION TASK
POPULATION TASK
• Deer control is a major issue in North Carolina
• We are going to work as small groups to figure
out the problems concerning deer
management
• We will also brainstorm solutions to the
problem.
POPULATION TASK
1) What are the effects of an overpopulation of
deer? Why is it a problem?
2) What are some natural ways to control the
deer population
3) What are some ways that humans can help
control the deer population?
Human Population and Impact
NC SCOS 5.03
Objectives
• We can analyze the growth patterns of the
human population
• We can explain the impacts of deforestation,
pollution, and resource overuse on the
environment
• We can inform the public about the dangers of
human impacts and how to avoid resource
overuse
Human Population
• Human population is currently about 6.8
billion
– Human population growth has been exponential
Population Pyramid Graphs
• Developing countries tend to have high
growth rates, whereas developed countries
tend to have stable growth.
– Population age distribution
• Larger at the bottom = more future growth
• Equal at each age = stable growth or even decline
• Population age distribution
• Larger at the bottom = more future growth
• Equal at each age = stable growth or even decline
Overpopulation: The Bad
• The problems with overpopulation include
abuse of resources:
– Deforestation
– Fossil Fuel Overuse
– Freshwater Overuse
– Pollution
– Lack of adequate food
– Non-native species
Deforestation
• Cutting down forests leads to a loss of
biodiversity: not as many different species in
an area
– Can affect local food webs, other species, and
even medicine!
Fossil Fuel Overuse
Burning Fossil Fuels
Excess CO2 in the air, traps
heat
Greenhouse effect enhanced
Global warming
Freshwater Overuse
• Poor water quality, not enough freshwater in
areas of need
• Polluted runoff from factories
Pollution
• Acid rain:
– Sulfur and nitrogen gases released from factories
into the air
– Sulfur dioxide: SO2
– Falls in rain drops, slowly impacts pH of water, soil,
etc.
Pollution
• Ozone Layer Destruction
– CFCs: chlorofluorocarbons – released into the air
through old refrigerator and spray cans, destroy
ozone layer.
– Low ozone leads to high UV radiation
– UV radiation: can cause skin cancer through
mutation
Why you should wear sunblock!
Food
• Lack of food sources
• Most important in poor, developing countries
Introducing Non-native species
• Putting species into new ecosystems that
aren’t supposed to be there
– The introduced species generally outcompete, or
do better, than the native species.
– Example: pythons in the everglades.
What Can We Do?
• Use renewable resources for energy
– Water, wind, solar, and geothermal energy
What Can We Do?
•
•
•
•
Reduce carbon dioxide emissions
Reduce water waste
Investigate factories and their pollution levels
Increase public awareness of the issues
What Can We Do?
• Promote sustainable practices
– Using renewable energy, rotating crops, avoiding
pesticides and toxins, making sure we keep fishing
populations high, conserve resources
Bioaccumulation
NC SCOS 5.03, 5.02b
Quick Vocabulary
• Autotroph: makes its own energy, a producer
• Heterotroph: gets its energy from somewhere
else, a consumer
Quick Vocabulary
• Accumulate: to gain over time
Bioaccumulation
• Bioaccumulation: the buildup of toxins in top
consumers after eating many smaller
organisms in a food web
– Also called biomagnification or bioamplification
Bioaccumulation
• Imagine that a toxin, a pesticide, was sprayed
on the grass in the food web below. It cannot
be released by the plant and is always stored.
http://www.ruralni.gov.uk/print/index/publications/press_articles/beef_and_sheep/archive-10/grass-attack.htm
Bioacummulation
• Each level of organisms above the grass in the
food web will accumulate more and more of
the toxin because they eat so much of the
level below them
• For example, the mouse eats a large amount
of grass, and stores all of the toxins in its body.
Then the snake eats many mice, storing all of
their toxins. Finally the hawk eats many
snakes and stores all of their toxins in its body
Bioaccumulation
Eats 10 snakes= 1g
Eats 100 mice = .1g
Eats 1,000 grasses = .001g
1 grass has 0.000001g
Bioaccumulation
Highest toxin levels
Even more toxin
More toxin, concentrated
Lots of toxin, spread out
Why is biomagnification a problem?
• What do you think?
– Depends on the type of toxin
– If the toxin is toxic, it might cause problems with
the functions of an organism
• Impairs reproduction
• Kills off members of a species
• Prevents organisms from reproducing
What happens to the food web?
• What do you think?
– Decreased top consumers means more low level
consumers
– More low level consumers means increased
amounts of the toxic toxin!
– The top level consumers don’t stand a chance!
• Are we top level consumers? Can this happen
to us?
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