9/12 Daily Catalyst
Pg. 16 10% Rule
1. Which organism is
both the predator and
the prey?
 a. A
 b. B
 c. C
 d. D
 2. What is the difference between a primary and secondary
consumer?
 3. True or False, The arrows indicate that organism C eats
organisms D.

9/12 Daily Catalyst
Pg. 16 10% Rule
1. Which organism is
both the predator and
the prey?
 a. A
 b. B
 c. C
 d. D
 C
 2. What is the energy source for all food webs?
 The sun
 3. True or False, The arrows indicate that organism C eats
organisms D.
 False, the arrow shows organism D eats organism C

9/12 Class Business
 Quiz
#4 on Friday
 Ecology Test Thursday, 9/18
 Ecology paper due Thursday, 9/18
 Presentations are next Friday for Extra
Credit

Sign up by today!
 Interim
extra credit
9/12 Agenda
 Daily
Catalyst
 Class Business
 10% rule notes
 Quiz #4
 Library work Time
Speedy Review!
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1. I am a mother to a lot of offspring. I will take care of
them for the first few weeks of life, then they are own their
own for survival. What type of curve is described?
Type II
2. In a habitat, abundant resources are available to a
newly developed population. What type of growth curve
is expected?
Exponential (J-curve)
3.In a food chain, this organism is essential for supplying
energy to consumers and also for itself. Name this type of
organism.
The producer
Speedy Review!
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4. I am an organism that is highly territorial and prefers to
be left alone. What type of dispersion will I show?
Uniform (like penguins)
5. True or false, two countries can have identical age
diagrams even if their population size is different.
False, if countries have different population sizes, then
they have to have different age diagrams!
They do not have the same number of people
9/12 Objective
Analyze
food webs by
predicting the impact of
the loss or gain of an
organism
Page
16 10% Rule
Food Webs
Most energy?
Least energy?
Key Point #1: Trophic Levels
are energy levels in a food
web
Energy Inefficiency
 Key
Point #2:
10% of energy is
 Only ____
passed from one trophic
level to the next.
1.0%
 Key
Point #3: The rest, 90%
HEAT
is given off as __________
 Key
Point #4: Called the
10% rule
_______
10%
100%
10% Rule
1%
10%
100%
0.1%
Who has the most energy in
this food web?
THE
PRODUCERS
Who has the least energy in
this food web?
THE TERTIARY
CONSUMER
(TOP OF THE
FOOD CHAIN)
Does the cougar get more
energy when it eats a fox or
when it eats mice?
WHEN IT EATS
THE MICE
Let’s practice math
What is 10%
of:
a.100
b.452
c.348.7
d.27.22
Answers:
a. 10
b. 45.2
c. 34.87
d. 2.722
Example 1
The ranches of the American
Midwest are full of grass. The grass
uses sunlight to grow. Cows and
rabbits graze on the grass.
However, the grass provides these
animals little shelter from wolves,
which eat the cows and rabbits.
Example 1
Wolves:
_____kcal
34.5
Cows and Rabbits:
________kcal
345.0
Grass: 3450kcal
Cougar: ________kcals
.0768
.768
Wolves: _______
kcals
Foxes:
_______kcals
7.68
76.8
Rabbits: ________
kcals
Pineapple bush: 768 kcals
Tell me what ya know!
 What
percentage of energy actually transfers
up each trophic level?
 A) 1%
 B) 10%
 C) 50%
 D) 100%
B
 The diagram shows an energy pyramid for an African savanna.
Which statement best describes the flow of energy in the
pyramid?
 A. The zebras have the least amount of energy
 B. The producers have the least amount of energy
 C. The lion has the least amount of energy
 D. All the organisms have an equal amount of energy
C
 Observations
of an ecosystem in Louisiana show that
organisms in the first trophic level have an energy intake
of 5,000 kilocalories per square meter per year
(kcal/m2/year). What is the energy intake for the third
trophic level of the same ecosystem?
 a.
50,000 kcal/m2 per year
 c. 50 kcal/m2 per year
b. 500kcal/m2 per year
d. 5.0 kcal/ m2 per year
 Observations
of an ecosystem in Louisiana show that
organisms in the fourth trophic level have an energy intake of
3.38 kilocalories per square meter per year (kcal/m2/year).
What is the energy intake for the second trophic level of the
same ecosystem?
 a. 3 kcal/m2 per
year
 c. 338 kcal/m2 per year
b. 33.8 kcal/m2 per year
d. 33, 680 kcal/ m2 per year
Homework
 Complete
the food chain homework.
There is a front and a backside!
 Work
time
Quiz #4
 Directions:
Silently and independently
complete the quiz #4: Answer every
question and try your best.
 Time: 15 minutes
 Noise: 0 (silent)
 Observations
of an ecosystem in Louisiana show that
organisms in the third trophic level have an energy
intake of 678 kilocalories per square meter per year
(kcal/m2/year). What is the energy intake for the
producer of the same ecosystem?
 a. 6.78 kcal/m2 per year
 c. 67.8 kcal/m2 per year
b. 678000.0 kcal/m2 per year
d. 67800 kcal/ m2 per year
Pretend that a
falcon enters the
ecosystem.
Falcons eat toads.
What will happen
to the snake
population?
A.
B.
C.
D.
E.
All will go extinct
Increase in size
Decrease in size
Stop eating toads
C
Imagine that a
population of
bears wanders
into the
ecosystem. Bears
eat foxes. What
will happen to the
squirrel
population?
A.
B.
C.
D.
E.
All will go extinct
Increase in size
Decrease in size
Move elsewhere
B