Period: ____ Name: ___________________________________ Teacher: ___________________
1. FOOD WEB
a. If an organism has an arrow
going away from it, it is being
eaten (Giving energy to another
organism)
b. If an organism has an arrow
going towards it, it is eating
another organism (Getting
energy from that organism)
c. If an organism has both arrows
(one going away and one going
towards it) it is eating an
organism and then is being eaten
by another organism
d. The organism that ONLY has
arrows going away from it means:
a. It does not get energy
from other organisms. It has to get energy from the sun. Therefore, a producer.
2. COMPETITION: THE FIGHT FOR RESOURCES
Competition occurs when 2 organisms need the same __resources__ in the same _space_
at the same __time. Competition can occur among_a species or_multiple species species.
Examples: *** _________________________________________________
*** _________________________________________________
Results of Competition: What will happen if 2 species use exactly the same resource in the
same way?
1. _____________________________________________________________
2. _____________________________________________________________
5. CARRYING CAPACITY
Carrying Capacity – the __largest_
number of individuals an environment
can support. Carrying Capacity changes
when there is an increase or decrease in
the number of organisms in an
environment.
a. What will happen to carrying capacity if a population was faced with drought?
b. What will happen to carrying capacity if producers were removed from the
population?
c. What will happen to carrying capacity if a predator was removed from the
population?
5. MAKE A FOOD CHAIN ON YOUR OWN:
a. Rabbits feed on seeds; Snakes eat rabbits and hawks eat snakes. Make a food chain.
b. What would happen to each of the following if seeds were removed from the above food
chain (increase or decrease)?
 Rabbit – ___________________
 Snake – ___________________
 Hawk – ___________________
 Carrying capacity- ___________________
 Will competition increase or decrease? ___________________
6. MAKE A FOOD PYRAMID ON YOUR OWN:
a. Fish feed on zooplankton; Zooplankton on algae and sharks feed on fish. Make a food
pyramid.
b. What would happen to each of the following levels if sharks became extinct (increase or
decrease)?
 Fish – ___________________
 Zooplankton – ___________________
 Algae – ___________________

EVALUATING CHANGES IN AN ECOSYSTEM:
The tree is an organism in our ecosystem that is being overused. It is used as firewood, paper,
lumber and other various duties. Replanting trees is an effort that will increase tree numbers, yet
the time to grow the trees cannot keep up with how quickly trees are being cut and used….
a. How can this decrease in trees affect our ecosystem?
People begin to replant trees in an effort to increase the number of trees in our ecosystem.
b. How would replanting trees affect the rest of the other biotic factors of our ecosystem?