Monday
TEK 12C: Analyze the flow of matter and
energy through trophic levels
using various models including food chains,
food webs, and ecological pyramids
Lesson frame:
•We will analyze the flow of energy and
matter through a food chain.
• I will complete the Looney Labels Food
Chain activity
•I will be able to correctly answer a food
chain question to show understanding.
What is the main source of
Energy w/in an Ecosystem?
The SUN!
It provides Energy for
the plants so that they
can undergo
photosynthesis and grow
and then animals eat
them.
Aut
trophs
“Auto” = self
“troph” = food
They are PRODUCERS!
Organisms that use
Energy from the
environment to make
their own food!
(e.g.; plants and some
bacteria)
Heterotroph
“Hetero” = other
“troph” = food
They are CONSUMERS!
Organisms that eat
Other organisms to
Obtain Energy.
(e.g.; mushrooms, leopards,
humans, & sharks)
Animals that eat
ONLY plants,
fruits, and
“herbs”
(e.g.; Fruit Bats, Moose,
Elephants, Rabbits,
Deer, Cows)
Omnivores
Animals that eat both
autotrophs &
heterotrophs (plants and
animals)
(e.g.; bears, most humans, pigs,
dogs, monkeys, ducks & crows)
Carnivores
Animals that eat other
heterotrophs
(animals)… Meat Eaters
ONLY!
(e.g.; Komodo Dragons, Lions,
Tigers, Snakes & Octopus)
Predator vs. Prey
Predator
Captures and feeds
Prey
Is eaten or fed on
Decomposers
Decomposers
Breaks down organic
matter and recycles
it back into the
earth (this makes
them the ultimate
top level consumer)
(e.g.; fungi/ mushrooms, and
bacteria)
Detritivores
Detritivores
Scavengers; Feed on
DEAD decaying
organisms
(e.g.; mites, flies, earthworms,
snails, crabs, rats & vultures)
Teacher: Model the LOONEY LABEL activity
Student: work on activity until teacher calls a
huddle
Huddle up!
Did we get it?
Answer the following questions
Food Chain
Shows how Energy is
transferred “thru” an
Ecosystem
Sun  Autotrophs  Heterotrophs
Some People
Shows a linear feeding
relationship for 1
particular organism
(“Who eats who”)
Arrows ALWAYS Point to the
1 who is Enjoying the Meal
Take it away Tuesday
TEK 12C: Analyze the flow of matter and energy
through trophic levels
using various models including food chains, food
webs, and ecological pyramids
Lesson frame:
• I can analyze the flow of energy from one trophic
level to another
• I can explain the flow of energy and the 10% rule
within food chains/webs/pyramids.
Food Web
Shows a NETWORK
of interconnected
feeding relationships
within an ecosystem
Food Webs are ALL
of the Food Chains
w/in an Ecosystem
linked together
(“Who eats who” and “whose being eaten”)
Food Web
Trophic Levels
Each step in a food chain or food web
– PRODUCERS REPRESENTS THE 1ST LEVEL
– CONSUMERS MAKE UP THE 2ND, 3RD, OR HIGHER LEVELS
Each consumer depends on the trophic level below it
for energy
Trophic Levels w/in A Food Web
Producers
Always start a food
chain or a food web;
plants or bacteria
Primary Consumers
eat the producers;
herbivores
Trophic Levels w/in A Food Web
Secondary Consumers
Eat the producers and
the primary consumers;
omnivores
Tertiary Consumers
Eat the secondary and
primary consumers;
carnivores = the top
Predator
Only 10 percent of the enerey stored in an
organism can be passed on to the next
trophic level. Of the remaining energy,
some is used for the organism’s life
processes, and the rest is
a.Used in reproduction
b.Stored as body fat
c.Stored as body tissue
d.Eliminated as heat
What is the function of bacteria in the food web?
a. Decomposer
b. Producer
c. Primary consumer
d. Secondary consumer
What to do
Wednesday
TEK 12C: Analyze the flow of matter and energy through trophic levels
using various models including food chains, food webs, and ecological
pyramids
And
11C: Summarize the role of microorganisms in both maintaining and
disrupting the health of both organisms and ecosystems
Lesson frame:
• I can analyze all 3 pyramids( energy/mass/numbers)
• I can explain the flow of energy and the 10% rule within food
chains/webs/pyramids.
• I can analyze the flow of energy from one trophic level to another
• I can explain how bacteria can help or harm both organisms and ecosytems
The Effects of Toxins in the Food Chain
http://www.youtube.com/watch?v=E5P-UoKLxlA
Biomass Pyramids
Biomass
total amount of
living tissue within a
given trophic level
The Pyramid
represents the
potential food
available for each
trophic level.
Pyramids of Numbers
http://www.vtaide.com/png/foodchains-mcq.htm
Based on the # of
organisms at each
trophic level.
There should always
be more producers
represented than
there are consumers
Energy Pyramids/ The Rule of 10
Only about 10% of
the ENERGY
available w/in 1
Trophic Level is
transferred to
organisms at the
trophic level above it
The rest of the Energy is
released in some form of
heat
(e.g.; when you eat a chicken wing
you are only going to absorb 10% of
it’s energy)
Tertiary
consumers
(human)
Usable energy available
at each trophic level
(in kilocalories)
Secondary
consumers
(perch)
Primary
consumers
(zooplankton)
Producers
(phytoplankton)
Heat
10
Heat
100
Heat
Decomposers
Heat
1,000
Heat
10,000
Fig. 3-15, p. 63
How do microorganisms maintain the
health of ecosystems?
•Some microorganisms are decomposers that break down organic
matter into smaller pieces, eventually releasing raw nutrients back
to the ecosystem.
http://www.youtube.com/watch?v=WLk-9ib0OVA
•Some bacteria convert nitrogen and other nutrients to forms that
can be used by primary producers (plants and other photosynthetic
organisms).
•Specialized “oil-eating” bacteria help restore ecosystems
following oil spills.
•Mycorrhizal fungi seem to help ecosystems recover following
disturbances.
How do microorganisms disrupt the
health of ecosystems?
• Populations of some usually harmless aquatic microorganisms,
including dinoflagellates and the photosynthetic protist Euglena (seen
here), can grow exponentially following an influx of nutrients. Such
responses to added nutrients are called algal blooms, and
they can be very harmful to ecosystems.
– Algal blooms can block sunlight and disrupt photosynthesis.
– Blooms of dinoflagellates, called red tides,
release toxins into the ecosystem.
– Increased rates of decomposition
following very large blooms can result
in dead zones, areas devoid of oxygen
that are inhospitable to multicellular life.
Why couldn‘t you survive a day
without bacteria?
•They process our wastes and make them usable again.
Without them – nothing would rot.
•They purify our water.
•Keep our soils productive
•Synthesize vitamins in our intestines
•Convert our food into useful sugars and polysaccharides
•Wage war on alien microbes that enter our digestive
system
•Pluck nitrogen from the air and convert it into useful
nucleotides and amino acids for us.
In general, which trophic level has the
most energy available to it?
a. Primary consumers
b. Producer
c. Secondary consumer
d. Tertiary consumer
The diagram is intended to show relationships in an ecosystem. What do the
arrows represent?
Lactose is a naturally occurring sugar found in milk.
Some dairy products, such as yogurt, may contain
live bacteria. These products are useful to people
who lack the ability to digest lactose. What does
this information demonstrate?
a. Bacteria raise the acidity of processed foods.
b. Some bacteria interfere with digestion.
c. Bacteria can prevent insulin production.
d. Some bacteria are beneficial to human health.
Thursday we
EAT/ DRINK/ AND
BE MERRYDuring the BEAR LAB
Limiting Factors
12 D: Recognize that long term survival of species is
dependent on changing resource basis that are limited.
(Students can recognize the effects of limited
resources in an environment.)
Lesson frame:
•We will recognize the effects of limited
resources in an environment.
• I will compete for food and water during the
bear activity.
•I will be able to correctly answer a limiting
factor question to show understanding.
Stem Questions:
•Suppose you could eat up to 12 times your body weight every
day like a hummingbird what would you do maintain your food
supply?
•Can you predict the outcome if fertilizers were banned?
•Can you assess the value of human disturbance within an
ecosystem?
•What choice would you have made if food was unlimited?
•How would you prioritize the effect of a decomposer in
replacing limiting factors back into the ecosystem?
•What would result if the amount of expected annual rainfall
in a desert were to decrease in half?
•How would you organize limiting factors to show the
difference between biotic and abiotic factors?
Reasons WHY we Compete to
Survive…
To Obtain:
1. Food
2. Living Space
3. Other Needs in
Life
“Competition”
Competitive Exclusion Principle
Says that in nature:
Direct competition
often results in a
“WINNER” and a
“LOSER,” w/ the losing
organism failing to
survive
What do we know about Populations?
All populations will GROW to their Carrying
Capacity as long as there is enough food,
shelter, & other necessities needed for life!
Carrying Capacity
the largest # of
individuals that an
environment can
support…
The # right before
there is not enough
food & space to go
around, and
individuals will start
to die off.
What else would cause a Population
to decrease?
Such as natural
disasters, human
disturbances,
disease, and
predation
Limiting Factor
A factor that causes the growth of a
population to decrease.
Examples
1.Space
2. Water
3. Food
4.Nutrients
Pre Lab Questions
1. What is the relationship between
competition and population size?
2. Identify how a limited resource can affect
the size of a population.
3. Give an example that illustrates this
situation.
Follow the instructions for the
Bear lab
Regroup later with your
teacher to answer some
questions and wrap up
An example of an abiotic
limiting factor affecting aquatic
organisms it the
Any abiotic or biotic
factor that controls the
number of individual in a
population is
a. A pollutant
b. Chemosynthesis
c. A bioaccumulation
indicator
d. A limiting factor
Competition for resources is a limiting factor
because
a. There is a limited amount of food and space
in most ecosystems
b. Predator/prey populations often increase
and decrease in cycles
c. Abiotic factor such as light and water are
present
d. Cities and highways provide alternate
environments for animals and plants
FRIDAY
HAVE STUDENTS USE THE STARBOARDS ON
THE CARBON CYCLE GAME AND NITROGEN
ANIMATION