Transcript Chapter 2: Principles in Ecology

Chapter 2:
Principles in
Ecology
2-1: What is ecology WARM UP
1.
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An ecosystem is a collection of
all the organisms that live in a
particular place, together with
their nonliving, or physical,
environment. Within an
ecosystem, there are several
levels of organization. Your
school and its grounds are
similar to an ecosystem.
What living things are found
in and around your school?
2. What nonliving things are
found in your school?
3. Into what large groups are the
students in your school
divided?
4. Into what smaller groups are
these large groups divided?
5. Are these groups ever divided
into even smaller groups? If
so, what are these groups?
EQ #1:What is Ecology?
A.
B.
Interactions and
Interdependence
Levels of Organization
C. Ecological Methods
1. Observing
2. Experimenting
3. Modeling
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Ecology = The
scientific study of
interactions among
organisms and
between organisms
and their
environment, or
surroundings.
EQ #2: How are the different levels of
organization of life related?
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Species (individual) = can breed and produce fertile offspring
Population = groups of individuals that belong to the same
species and live in the same area.
Community = different populations that live together in a defined
area.
Ecosystem = a collection of all the organisms that live in a
particular place, together with their nonliving, or physical,
environment.
Biome = A group of ecosystems that have the same climate and
dominant communities.
Biosphere = Contains the combined portions of the planet in
which all of life exists, including land, water, and air or
atmosphere.
EQ#3: What types of ecological Methods do
ecologists use to study the living world?
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Observing
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Experimenting
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Modeling
All of these methods
rely on the application
of scientific methods
to guide ecological
inquiry.
Check for Understanding
1.
2.
3.
List the six different levels of organization that
ecologists study, in order from smallest to
largest.
Describe the three basic methods of ecological
research.
Identify two ways in which you interact with
each of the three parts of the biosphere every
day: land, water, and air.
2-2 : Energy Flow WARM UP
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Energy flows in one direction
through an ecosystem, from
the sun or inorganic
compounds to producers
(organisms that can make their
own food) through various
levels to consumers
(organisms that rely on other
organisms for food). Your body
gets the energy and materials
it needs for growth and repair
from the foods you eat.
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Make a list of five foods that you
like to eat. Indicate whether the
food comes from a plant
(producer) or an animal
(consumer).
Like many birds, chickens eat
grains, which are seeds. Where do
seeds come from?
Meat comes from beef cattle.
What do cattle eat?
Construct a diagram showing how
one of your favorite foods obtains
its energy. Include as many levels
as you can.
EQ #4: How does energy flow
through the biosphere?
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Sunlight is the main energy
source for life on Earth.
Some types of organisms rely on
the energy stored in inorganic
chemical compounds
Energy Flow Through the Biosphere
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Autotrophs = Use energy from the
environment to make their own food.
(Producers)
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Ex: plants, some algae and some bacteria.
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Photosynthesis = Adds oxygen to the environment
and remove carbon dioxide. Glucose is also produced.
Chemosynthesis = when organisms use
chemical energy to produce carbohydrates.
Consumers
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Organisms that rely on other organisms
for their energy and food supply
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Heterotrophs (consumers)
Consumers:
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Herbivores = eat only plants
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Carnivores = eat animals
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Omnivores = eat both plants and animals
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Detritivores = eat plant and animal remains
and other dead matter (detritus)
Decomposers = breaks down organic matter
EQ #5: What happens to the energy in an
ecosystem when one organisms eats another?
Energy flows through an
ecosystem in one direction
Sun or inorganic compounds 
producers  consumers
 Food chains = show oneway flow of energy
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Food webs = links food
chains
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Trophic levels = steps in
food chains or food webs.
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Energy
Pyramids
step = trophic level.
Show energy movement
through the environment.
 Only 10% available to next
level
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Energy
decreases as
you go up the
pyramid
Draw this pyramid
(Omnivore)
Heterotroph
(Carnivore)
(Herbivore)
(Autotroph)
Pyramid of Numbers
Shows the relative
number of individual
organisms at each
trophic level.
Energy Pyramid
Shows the relative
amount of
energy available at each
trophic
level. Organisms use
about 10
percent of this
energy for
life processes.
The rest is lost
as heat.
Biomass Pyramid
Represents the amount of
living organic matter at each
trophic level. Typically, the
greatest biomass is at the
base of the pyramid.
Figure 54.13 A pyramid of numbers
Why does the number of organisms decrease as you go up
the pyramid?
Figure 54.14 Food energy available to the human population at different trophic
levels
Why must humans consume more food?
Check for Understanding:
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What are the two main forms of energy that
power living systems?
Briefly describe the flow of energy among
organisms in an ecosystem
What proportion of energy is transferred from
one trophic level to the next in an ecosystem?
FOOD WEB PRESENTATION 25 Pts
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5 pts. The food web
must contain at least five
food chains consisting of
a producer, a primary
consumer, and a
secondary consumer.
5 pts. Each consumer
must be labeled as an
herbivore, carnivore,
omnivore, or decomposer.
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5 pts. At least one
predator-prep relationship
must be shown.
5 pts. Five abiotic factors
(non-living) also must be
included and labeled.
5 pts. You will need to
explain your poster to the
class in oral
presentations.
2-3 Cycles of Matter:
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EQ: How does matter cycle among the living and
nonliving parts of an ecosystem?
EQ: What would happen to a living system that
was nutrient deficient?
How does the availability of nutrients affect the
productivity of ecosystems?
It’s Raining, It’s Pouring
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How many times have you
had to change your plans
because of rain? It
probably didn’t help if
someone tried to cheer you
up by saying, “But we
really need the rain.”
However, rain is important.
If it didn’t rain, how would
living things on land get
water?
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When rain falls on the ground, it
either soaks into the soil or runs
across the surface of the soil.
When rainwater runs across the
land, what body of water might
collect the rain?
From here, where might the
water flow?
After the rain, the sun comes out
and the land dries. Where does
the water that had been on the
land go?
Construct a diagram that would
illustrate all the places a molecule
of water might go. Begin with a
raindrop and end with a cloud.
Recycling in the Biosphere:
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Unlike the one-way flow of energy, matter
is recycled within and between
ecosystems.
Biological systems do not use up matter,
but transform it.
Nutrient Cycles:
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Organic Nutrients- CHNOP
Every living organism needs
nutrients to build tissues and
carry out essential life
functions.
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Water Cycle
Carbon Cycle
Like water, nutrients are
passed between organisms
and the environment through
biochemical cycles.
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Nitrogen Cycle
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Phosphorus Cycle
Video cliphttp://www.unitedstreaming.co
m
The Water Cycle
All living things require
water to survive. Where
does it all come from?
Evaporation
Condensation
Precipitation
Transpiration
Runoff
Seepage
Root
Uptake
It moves between the ocean,
atmosphere, and land.
This figure shows how water molecules can change forms and be
used through evaporation (change from liquid to gas) and transpiration
Go(by
to evaporating from the leaves of plants).
Section:
The Carbon Cycle:
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Biological processes, such
as photosynthesis,
respiration, and
decomposition of plants
and animal
Geochemical processes,
such as the release of
carbon dioxide (CO2) gas
to the atmosphere by
volcanoes
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Mixed biogeochemical
processes, such as the
burial of carbon-rich
remains of organisms and
their conversion into coal
and petroleum (fossil
fuels) by the pressure of
the overlying earth
Human activity, including
mining, the burning of
fossil fuels, and the
cutting and burning of
forests.
The Carbon Cycle
CO2 in
Atmosphere
CO2 in Ocean
Nitrogen Cycle
Is driven primarily by the
activities of unicellular
organisms in the soil and
oceans.
1. Nitrogen is in the atmosphere all the time.
2. Bacteria change the nitrogen gas into nitrates (ammonium), which is a
kind of natural fertilizer taken in by the roots of plants and trees and
used to build plant protein. This process of change is called nitrogen
fixation.
3. Animals then eat the plants with protein in them
4. Animal and plant waste then releases protein into the soil through
decomposition.
5. Finally, more kinds of bacteria break down plant protein to a form that
releases nitrogen back into the atmosphere. This process is called
denitrification
The Nitrogen Cycle
N2 in Atmosphere
NH3
NO3and NO2-
Phosphorus Cycle
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Phosphorus is essential to living organisms
because it forms part of important life-sustaining
molecules such as DNA and RNA.
Phosphorus does not enter the atmosphere like
oxygen, carbon and nitrogen
phosphorus remains mostly on land in rock and
soil minerals, and in ocean sediments
Phosphorus Cycle
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When plants absorb
phosphate from the soil
or from water, the plants
bind the phosphate into
organic compounds.
Organic phosphate moves
through the food web,
from producers to
consumers, and to the
rest of the ecosystem.
Nutrient Limitation
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Primary productivity – rate at which
organic matter is created by producers
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Controlled by the amount of available
nutrients
Limiting nutrient – when an ecosystem is
limited by a single nutrient that is scarce or
cycles very slowly.
Checkpoint!!!!
1. How does the way tat matter flows through an
ecosystem differ from the way that energy flows?
2. Why do living organisms need nutrients?
3. Describe the path of nitrogen through its
biogeochemical cycle.
4. Explain how a nutrient can be a limiting factor in an
ecosystem.