Transcript Document

Interactions
Within
Communities
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1. The three major types of
interaction among organisms in an
ecosystem are
competition,
predation, and
symbiosis.
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2. Competition is the struggle
between organisms that attempt to
use the same limited resources.
Organisms that are better at
competing are more likely to get and
use the available resources.
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3. Resources are the things that
organisms obtain from their
environment in order to survive.
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They include food, water and shelter.
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Some resources are limited.
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4. Predation is an interaction in
which one organism captures and
feeds on another organism for food.
The organism that does the killing is
the predator.
The organism that is eaten as food is
the prey.
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5. Predators generally have traits
that enhance their ability to capture
prey, such as fast speed, keen
eyesight, and sharp teeth.
6. Prey have traits that help them
avoid being captured, such as the
ability to escape quickly or to hide in
the environment. Some prey have fur
or skin colors and patterns to help
them blend in to their environment.
They are camouflaged.
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Which one is the predator
and which one is the prey?
zebra
lioness
Which one is the predator
and which one is the prey?
hare
fox
Which one is the predator
and which one is the prey?
fish
osprey
Which one is the predator
and which one is the prey?
snake
roadrunner
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7. Populations of predators and prey
typically follow a pattern over time.
At some point, the prey population
grows so large that prey are easy to
find.
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In turn, the predator population
grows because they have a good
supply of food.
As the predator population grows,
they continue to feed on prey.
This causes the prey population to
decrease.
Hares and Lynx Populations
90
Hares (x1000)
Lynx(x1000)
Number of pelts in thousands
80
70
60
50
40
30
20
10
0
1900
1902
1904
1906
1908
1910
Year
1912
1914
1916
1918
1920
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As the food supply decreases, the
large population of predators can no
longer be supported.
Then, the predator population
decreases.
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Then, the predator population
decreases.
When there are fewer predators, the
prey population can grow and the
cycle repeats.
Hares and Lynx Populations
90
Hares (x1000)
Lynx(x1000)
Number of pelts in thousands
80
70
60
50
40
30
20
10
0
1900
1902
1904
1906
1908
1910
Year
1912
1914
1916
1918
1920
symbiosis
8. What is a close
relationship between two
organisms that benefits at
least one of the species?
9. What are the
different kinds of
symbiosis?
Mutualism
Commensalism
Parasitism
11. Go to the 3rd picture on the top
row.
 Rhizobium bacteria live in small
growths called _________________
on the roots of _____________ such
as beans, peanuts, and soybeans.
The bacteria get their nutrients from
the plant’s roots and the plant is
supplied with abundant
________________ compounds.
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http://www.vtaide.com/png/symbiosis.htm
11. Go to the 3rd picture on the top
row.
 Rhizobium bacteria live in small
growths called nodules on the roots
of legumes such as beans, peanuts,
and soybeans.
 The bacteria get their nutrients from
the plant’s roots and the plant is
supplied with abundant nitrogen
compounds.
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http://www.vtaide.com/png/symbiosis.htm
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12. Go to the 4th picture on the top row.
An ___________ and a _______________
combine to form a lichen.
The _______ produces food for the
___________________.
The fungus provides ______________ for
the alga.
http://www.vtaide.com/png/symbiosis.htm
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12. Go to the 4th picture on the top row.
An alga and a fungus combine to form a
lichen.
The alga produces food for the fungus.
The fungus provides moisture/water for
the alga.
http://www.vtaide.com/png/symbiosis.htm
10. Mutualism
both
organisms
benefit
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This is a “win-win” situation because both
organisms get something helpful from
the relationship.
Think about teammates. They work
together and help each other to try to
win a competition.
13. Commensalism
This is a “win-draw”
situation because only one
organisms get something
helpful from the
relationship. The other is
not harmed, but it is not
helped, either.
Think about neighbors. They help each other
out sometimes. They may borrow some sugar
or a lawn mower. It doesn’t hurt you or help
you.
one organism
benefits
one organism
is unaffected
+0
one organism
benefits
one organism
This is a “win-lose” situation is harmed
14. Parasitism
because one organism gets
something helpful from the
relationship, but the other
one is harmed.
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A parasite is basically a thief! They
steal something (often blood or food)
from the other organism.
Parasitism
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(10). The organism that
benefits in a parasitic
relationship is called the
parasite.
The organism that is harmed
in a parasitic relationship is
called the host.
Common
Parasites
Example 1:
Moray Eel with
Cleaner Fish
Moray eel gets
a clean mouth.
Cleaner Fish
gets a meal.
Mutualism: both
benefit
Example 2:
Cattle with cattle egrets
Cattle stir up
insects as
they eat
grass.
Egrets hang
around and
eat insects.
Commensalism: one benefits,
one is unaffected
Example 3:
Tick
on
a
dog
Ticks feed on the
blood of their
hosts.
Dog may contract
diseases like
Lyme disease and
Rocky Mountain
spotted fever
and become
Parasitism: one
anemic or
paralyzed.
one is harmed
benefits,
Example 4:
Clown fish with anemone
Clown fish
gets
protection.
Anemone is
unaffected.
Commensalism: one benefits,
one is unaffected
Example 5:
Antelope with Oxbird
Antelope
gets rid of
parasites.
Oxbird
gets a
meal.
Mutualism: both
benefit
Example 6:
Taenia worm in human
eye
Worm
infects
human
blood
stream.
Human
may go
blind.
Parasitism: one benefits,
one is harmed
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Taenia saginata, also known as the beef
tapeworm, is a parasite of both cattle and
humans, causing taeniasis in humans.
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Taenia saginata occurs where cattle are
raised by infected humans maintaining
poor hygiene, human feces are improperly
disposed of, meat inspection programs are
poor, and where meat is eaten without
proper cooking.
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Cattle become infected from ingesting the
eggs making them an intermediate host.
Humans become infected by ingesting raw
or undercooked infected meat, making
them the host.
Taenia saginata infestations occur
worldwide, however, only 1% in the
United States.
The disease is relatively common in Africa,
some parts of Eastern Europe, the
Philippines, and Latin America.
Example 7:
Acacia plant with ant galls
Bull horn acacia
trees provide
nutrients and
housing for
acacia ants.
Acacia ants
attack herbivores
that try to eat the
leaves.
Mutualism: both benefit.
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Some types of acacia trees have evolved special
structures to support acacia ant colonies…The
trees also excrete nectar for ant food and have
swollen hollow thorns that can be used for nest
sites.
The trees produce not only nectar but also
special oil- and protein-rich nodules on their
young leaf tips. The orange bodies on the tips of
new leaflets are used only to feed the ants.
These provide all the nutrition the ant colony will
ever need. To allow the tree better growing
opportunities, the ants even trim away weeds
from its base.
In return, the ants, which are equipped with
powerful stingers, attack caterpillars and deer
and any other animals that try to eat the acacia
leaves.
Mr. Lee “Symbiosis”
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YouTube - Mr. Lee - Symbiosis rap