Name _____________________________
Period _______
Ecosystem Study Guide/ Review Pack
Section 1: Multiple choice
1. A territory is ___________
a. A place where one animal lives
b. An area defended by one or more individuals
c. A behavior resulting from interspecific competition
d. A behavior resulting from commensalism
2. Bacteria in your intestines are an example of mutualism if they
a. Make you sick
b. Have no effect on you
c. Are destroyed by digestive juices
d. Help you break down food
3. What can occur if a population has plenty of food and space, and has no competition
of predators?
a. Reduction of carrying capacity
b. Zero population growth
c. Exponential growth
d. Coevolution
4. Two species in an area eat the same type of plant but feed off the plant at
different heights. This is an example of
a. Intraspecific competition
b. Commensalism
c. Resource partitioning
d. Symbiosis
5. If exponential growth occurs in the population of a species of predators, the
population of its prey will most likey
a. Decrease quickly
b. Increase slowly
c. Stay the same
d. Experience exponential growth
6. The carrying capacity of an environment for a particular species at a particular
time os determined by
a. Number of individuals in the species
b. Distribution of the population
c. Reproductive potential of the species
d. Supply of the most limited resources
7. Which of the following examples would be least likely to considered a symbiotic
interaction?
a. A wren builds a nest in a cactus
b. A yucca moth pollinates and lay eggs on yucca flowers
c. A kit fox hunts and feeds on a kangaroo rat
d. Bacteria in a fox’s digestive system help it digest food.
8. Coral snakes are very deadly black white and bright orange. The scarlet king snake
has the same coloring and markings as the coral snake but is harmless. This is an
example of_______.
a. Commensalism
b. Interspecific competition
c. Batesian Mimicry
d. Mullerian Mimicry
9. Which of the following is abiotic?
a. Bacteria
b. Rocks
c. Fungus
d. Tree
10. Ecotones are usually caused by__________
a. Pollution
b. Animals that live in the area
c. Human interaction
d. Soil nutrients
11. Passion butterfly, orange tiger butterfly, and Julia Butterfly are all bright orange.
All three of them have very bitter taste to their prey. What is this an example of?
a. Batesian mimicry
b. Mullerian mimicry
c. Commensalism
d. Parasitism
Section 2: Short Answer
1. How many trophic levels are shown in the food chain above?
2. How much energy is lost as you move up each trophic level?
3. Explain why you would expect to find fewer hawks than frogs in an ecosystem.
4. Which species in the food web above is a generalist (according to the food web?)
a. turtle
b. heron
c. alligator
d. frog
5. Which species would be most affected by a decline in carp (alligator or heron)?
Explain your answer.
6. List three direct effects that would occur if the population of carp increased?
(each affect should be a different type of relationship)
7. What is the ecological term used to describe the location where the arrow is
pointing?
8. Why would you find more diversity in this area
9. Explain the difference between a k-selected species and a r-selected species based
on the following factors:
K selected
Life span
Growth rate
Sexually mature
# offpring
example
r-selected
10. Label the type of symbiosis in each scenario:
Animals
Barnacle/Whale
Cuckoo/ Warbler
Honey guide bird/
Badger
Remora/ shark
Yucca plant/yucca
moth
Wrasse fish/ black
sea bass
Description of Relationship
Relationship
Barnacles create home sites by attaching
themselves to whales. Whale is neither harmed
nor benefited
A cuckoo may lay its eggs in the warbler’s nest.
The cuckoo’s young will displace the warbler’s
young, and the warbler will raise the cuckoo’s
young.
Honey guide birds alert and direct badgers to
beehives. The badgers then expose the hives
and feed on the honey first. Next the honey
guide birds eat.
Remoras attach themselves to a shark’s body.
They then travel with the shark and feed on the
leftover food scraps from the shark’s meals.
This relationship neither harms nor benefits the
shark.
Yucca flowers are pollinated by yucca moths.
The moths lay their eggs in the flowers where
the larvae hatch and eat some of the developing
seeds.
Wrasse fish feed on the parasites found on the
black sea bass’s body.
Bee/ marabou stork
The stork uses its saw-like bill to cut up the
dead animals it eats. As a result, the dead
animal carcass is accessible to some bees for
food and egg laying. The stork is neither
benefited or harmed
Deer/ tick
Ticks feed on deer blood to the deer’s detriment
Section 3: Case Studies
Case Study 1
Two species of monkeys are introduced to an island that provides them an ideal habitat.
One species is arboreal and eats fruits, insects, and leaves at the top of the tree; the
other is terrestrial and relies on fallen fruits and a few small insects it can pick up for the
ground for survival. The monkeys have an abundance of food, no local competition for the
food, and no predators. After a decade, the number of arboreal monkeys increased faster
than the terrestrial fruit and insect eaters. Some of the arboreal monkeys move closer to
the ground to obtain food. After 20 years, the numbers of terrestrial monkeys on the
island start to decrease rapidly, although the arboreal monkey populations steadily
increase. Ecologist notice that the food supply for the monkeys is slowly declining due to
the increase of the arboreal monkeys. Eagles were introduced to the ecosystem. The
eagles are predators of the arboreal monkeys. Over the next 20 years, the number of
arboreal monkeys decrease and the number of terrestrial monkeys slowly increase.
1. Explain the three parts of the Law of Competitive Exclusion.
How are the two species of monkeys following the Law of Competitive Exclusion?
2. Both species of monkeys eat the same type of food. When the two species were
first introduced to the island, one species found food high in the trees and the
other species found food lower to the ground. What is this an example of?
3. What type of competition exists between the following:
arboreal monkey- arboreal monkey:
arboreal monkey- terrestrial monkey:
4. What type of competition is more intense? Why?
5. Who were better competitors for resources? Arboreal monkeys or terrestrial
monkeys? Why?
6. Why would a boom and bust have occurred in the arboreal monkeys if the eagle
species was never introduced to the island?
7. Which species is a keystone species? arboreal monkey, terrestrial monkey, or
eagle? Why?
8. Which graph shows the relationship between the two species of monkeys when they
live together?
9. Which graph shows the relationship between the arboreal monkey and the eagles?
Graph A
Graph B
Case Study 2
The cardon and organ-pipe are flowering cacti that depend on bats for pollination. The
bats pollinate the cacti as they eat the nectar in the caci’s flowers and spread its seeds
when they eat the cactus fruit. Studies of the cacti show that they are not producing as
much fruit as they should. It was also noted that bats living near these cacti had been
driven away from their caves.
1. What is the relationship between the bats and the cacti?
2. How did the reduction in the number of bats affect the cacti?
3. Give an explanation involving tolerance limits that would have caused the bats to be
driven away.
Section 4: Questions from the textbook
Read pages 50-67 in your text books and answer the questions below
1. What is the critical factor for the Saguraros?
2. What would the following scenario indicate about an ecosystem
Many trout in a lake begin dying
3. Does generalist or specialist have the following characteristics: low reproductive
rate and care for their young for a long period of time?
4. How can so many different species of finches live in the Galapagos Island without
competing with each other for food?
5. What is the difference between intraspecific competition and interspecific
competition?
6. What are three ways intraspecific competition can be decreased?
7. Give one example of the coevolution of a predator prey relationship.
8. Read each statement. Does the statement best describe a r-selected species or a
k-selected species?
_______Does little to provide care for offspring
_______Mature slowly
_______Rat
_______Elephant
_______J-growth curve
_______S-growth curve
9. Why do ecotones or edge effects often rich in species diversity?