Download Ch 3-4 study guide ANSWERS

Name
3.1 What Is Ecology?
Date __________
1. What is ecology? Study of the interrelationship between organisms and their
environment
2. What is the biosphere? Does it include abiotic, biotic or both? Biosphere
consists of al the parts of the planet in which all life exists –all organisms
and the physical environment of the Earth
biosphere
biome
ecosystem
population
Individual/species
4.
community
Label each level of organization on the diagram above.
5. Explain the relationship between ecosystems and biomes. Ecosystems = all the
biotic and abiotic components and a biome consists of a group of ecosystems
that share similar climates and similar organisms
6. Define the terms abiotic and biotic (within the Venn diagram below). Then use
the terms in the box to fill in the Venn diagram. List parts of the environment
that consist of biotic factors, abiotic factors, and some components that are a
mixture of both.
air
heat
animals
bacteria
mushrooms
plants
precipitation
soil
sunlight
Both
Biotic
Factors
LIVING
Animals
Plants
Mushrooms
Bacteria
NONLIVING
Soil
Sunlight
Heat
Precipitation
Air
Abiotic
Factors
7. Why are many ecological phenomena difficult to study?
They occur over long periods of time and over large areas of land/water
8. Why do ecologists make models?
To gain insight into complex phenomena
3.2 Energy, Producers, and Consumers
1. What do autotrophs do during photosynthesis?
Use light energy from the sun to convert carbon dioxide and water into
food (carbohydrates –glucose) and release oxygen
2. Can some organisms survive without energy from the sun? Explain your
answer.
Yes, some chemosynthetic organisms can make food from chemical
compounds – ex. some bacteria that live very deep in the ocean can use
hydrogen sulfide to make food
3. Can organisms create their own energy? Explain your answer. No –
autotrophs can get energy from the sun (photoautotrophs) OR from
chemicals (chemoautotrophs)
4. Complete the table about types of heterotrophs.
Types of Heterotrophs
Type
Definition
Examples
Type of
Consumer
Herbivore
Definition
Example
Eats plants
Cow
Carnivore
Eats other animals
Snake
Omnivore
Eats both plants and animals
Human
Scavenger
Eats carcasses of other animals – but
Vulture
does not typically kill them
themselves
Detritivore
Feed on dead matter
Earthworms
Decomposer
Break down organic matter
Bacteria/Fungi
5. What is a consumer?
Organisms that eats other organisms for food/energy aka heterotrophs
6. How would you categorize a consumer that usually catches and eats prey,
but also eats dead animal carcasses? carnivore
Food Chains and Food Webs
1. Complete the table about feeding relationships.
Feeding Relationships
Relationship
Description
Food Chain
Organisms transfer E by eating and being eaten (steps)
Food Web
Network of complex interactions form by feeling relationships in an
ecosystem
Use the food chain to answer Questions 2–4.
2. Draw arrows between the organisms to show how energy moves through this
food chain. Write producer, herbivore, or carnivore under each organism.
Explain how energy flows through this food chain. Phytoplankton (primary
producer)  zooplankton (primay consumer)  small fish  squid  shark
Quaternary consumer
(carnivore)
Tertiary consumer
(carnivore)
Primary consumer
(herbivore)
Secondary consumer
(carnivore)
Primary
producer
What would happen to this food chain if a disturbance caused a serious
decline in the shark population? Increase in number of squid therefore a
decrease in the number of fish, eventually, there will not be enough fish
to feed squid and they will decrease as well.
Trophic Levels and Ecological Pyramids
Write True or False on the line provided.
F
6. Primary consumers always make up the first trophic level in a
food web.
PRODUCERS
T
7. Ecological pyramids show the relative amount of energy or matter
contained within each trophic level in a given food web.
F
8. On average, about 50 percent of the energy available within one
trophic level is transferred to the next trophic level. 10% REST
IS LOST AS LOW GRADE HEAT
F
9. The more levels that exist between a producer and a given
consumer, the larger the percentage of the original energy from
producers is available to that consumer
Use the diagram to answer Questions 10–17.
Match the organism with its trophic level. A trophic level may be used more
than once.
Organism
Trophic Level
A
10. algae
A. primary producer
B
11. grasshopper
B. first-level consumer
A
12. marsh grass
C. second-level consumer
D
13. marsh hawk
D. third-level consumer
C
14. plankton-eating fish
B
15. ribbed mussel
C
16. shrew
B
17. zooplankton
18. Complete the energy pyramid by writing the source of the energy for the
food web and how much energy is available to first-, second-, and thirdlevel consumers.
.1%
1%
10%
For Questions 19–21, complete each statement by writing the correct word or
words.
18. A pyramid of BIOMASS illustrates the relative amount of living organic
matter available at each trophic level in an ecosystem.
19. A pyramid of NUMBERS shows the relative numbers of individual organisms
at the trophic levels in an ecosystem.
20. A pyramid of ENERGY _ shows the relative amounts of energy available at the
trophic levels of a food chain or food web
3.4 Cycles of Matter
Recycling in the Biosphere
For Questions 1–3, write True if the statement is true. If the statement is
false, change the underlined word or words to make the statement true.
F CARBON 1. The four elements that make up over 95 percent of the body in
most organisms are oxygen, sulfur, nitrogen, and hydrogen.
TRUE
2. Matter moves through an ecosystem in cycles.
F LIGHTNING 3. Chemical and physical processes include the formation of
clouds and precipitation, “burning” food, and the flow of
running water.
7. What role do plants play in the water cycle?
PLANTS ABSORB GROUND WATER THROUGH THEIR ROOTS AND RERELEASE IT OT THE ATMOSPHERE DURING TRANSPIRATION
Nutrient Cycles
9. Complete the chart about the carbon cycle.
Processes That Cause Carbon to Move into
the Atmosphere
Process
Respiration
Volcanic activity
Description
Processes That Cause Carbon to Move
out of the Atmosphere
Process
Release of carbon dioxide Respiration
by an organism after
eating
the release of CO2 and
other gases into the
atmosphere through
vents in Earth's crust
Dissolving
Description
Release of carbon
dioxide by an organism
after eating
Carbon dioxide
dissolves in water
For Questions 10–12, write the letter of the correct answer on the line at the left.
B
10. The carbon in coal, oil, and natural gas came from
A. the combustion of fossil fuels.
B. the remains of dead organisms.
C. carbon-fixing bacteria in
swamp soil.
D. carbon dioxide dissolved in ocean water.
A
11. How does most of the carbon in an organism’s body return
to the environment after the organism dies?
A. Decomposers break the body down into simpler
compounds.
B. Heat from the sun causes the carbon in the body to
evaporate.
C. Geological processes cause the body to turn into a fossil
fuel.
D. Rainwater dissolves the carbon in the body and carries it to the
ocean.
A
12. Human processes mainly contribute to the
A. release of carbon dioxide into the atmosphere.
B. decrease of the total amount of carbon found on Earth.
C. depletion of carbon dioxide reserves in the atmosphere.
D. increase in the amount of carbon contained in rock materials.
Write True if the statement is true. If the statement is false, change the
underlined word or words to make the statement true.
T
found in soil.
13. Nitrogen, in the form of ammonia, nitrate, and nitrite, is
F AMMONIA 14. Nitrogen fixation is the process in which certain bacteria
convert nitrogen gas into nitrates.
T
15. Denitrification is the process by which some soil bacteria
convert nitrates into nitrogen gas.
F PROTEINS
16. All organisms require nitrogen to make amino acids, which
in turn are used to build carbohydrates.
T
17. Phosphate is released as rocks and sediments wear down.
T
18. Plants absorb phosphate from the soil or from water.
F Nitrogen
19. Phosphorus is the most abundant gas in the atmosphere.
CO2
20. Organic phosphate is taken up by producers during
photosynthesis and released by cellular respiration.
T
21. Phosphorus forms part of the important life-sustaining
molecules such as DNA and RNA.
SOIL
22. Plants absorb phosphorus from the atmosphere or water
23. List and describe the biological steps in the nitrogen cycle.
BACTERIA CONVERT ATMOSPHERIC N  AMMONIA (NITROGEN FIXING
BACTERIA OR NITROGEN FIXATION), OTHER BACTERIA CONVERT AMMONIA 
NITRATES AND NITRITIES WHICH CAN BE USED BY PRODUCERS (PLANTS)
CONSUMERS THEN EAT PLANTS OR OTHER ORGANISMS THAT EAT PLANTS.
DECOMPOSERS BREAK DOWN DEAD ORGANISMS AND RELEASE N BACK TO SOIL
24. What is atmospheric nitrogen fixation, and how does it affect organisms?
LIGHTNING CONVERTS ATMOSPHERIC N  USEABLE FORM
25. How do humans add nitrogen to the biosphere? FERTIILZERS
26. Which parts of the phosphorus cycle are geological processes?
GEOLOGICAL PROCESSES TURN MARINE SEDIMENT INTO ROCK AND
WASHES PHOSPHATE FROM ROCK INTO SOIL A. all the organisms in one area and their
Match the term with its definition.
Term
D
1. nutrient
B
2. chemosynthesis
C
3. consumer
A
4. ecosystem
H
5. photosynthesis
F
6. ecology
E
7. primary producer
G
8. Biosphere
physical environment
B. a process in which producers use
chemical energy to make carbohydrates
C. an organism that feeds on other
organisms
D. a chemical substance that an organism
needs to survive
E. an organism that uses chemical or light
energy to produce its own food supply
F. the study of the biosphere
G.
the portion of Earth and its atmosphere
that contains organisms
H. a process in which producers use light
energy to make carbohydrates
For Questions 9–12, complete the analogies.
9. omnivore : human :: carnivore : LION (VARY)
10. detritivore : earthworm :: herbivore : ZEBRA/COW (VARY)
11. autotroph : heterotroph :: phytoplankton : ZOOPLANKTON
12. biotic factor : elephant :: abiotic factor : RAINFALL
13. What is the difference between a food chain and a food web?
FOOD CHAIN SERIES OF STEPS (WHAT EATS WHAT), FOOB WEB
CONSISTS OF COMPLEX INTERACTIONS BETWEEN MANY ORGANISMS
IN AN ECOSYSTEM
Complete each statement by writing the correct word or words.
14. There are several hundred squirrels living in an oak forest. The squirrels
make up a(n) POPULATION.
15. Fungi and some kinds of bacteria are DECOMPOSERS that obtain nutrients
by chemically breaking down organic matter.
16. Ecologists measure BIOMASS in grams of organic matter per unit area.
17. In a process known as DENITRIFICATION, some types of soil bacteria
obtain energy by converting nitrates into nitrogen gas.
4.1 Climate
A
1. What effect do carbon dioxide and methane have on Earth’s
temperature?
A. They trap heat in the atmosphere.
B. They release heat from the atmosphere.
C. They block heat from entering the ocean.
D. They block heat from reaching Earth’s surface.
D
effect?
2. How would the temperature on Earth change without the greenhouse
A. The temperature at the equator would be warmer.
B. The temperature would stay the same.
C. It would be 30°C warmer.
D. It would be 30°C cooler
4.2 Niches and Community Interactions
3 What is a niche?
A niche is the range of physical and biological conditions in which a species lives and the way the
species obtains what it needs to survive and reproduce (its “occupation”).
4. Three different warbler species live in the same tree. One species feeds at the
top of the tree, the second species feeds in the middle part of the tree, and the
third species feeds at the bottom of the tree. Do all three species occupy the
same niche? Explain.
Since each warbler is utilizing resources in a different part of the tree, they do not occupy the sam
niche.
Competition
For Questions 4–8, write True if the statement is true. If the statement is false, change
the underlined word or words to make the statement true.
T
resources.
5. Competition occurs when organisms attempt to use the same
INTRASPECIFIC
SPECIES
T
T
6. Competition between members of the same species is known
as interspecific competition.
7. The competitive exclusion principle states that no two
organisms can occupy exactly the same niche in exactly the same
habitat at exactly the same time.
8. If two species of bacteria are grown in the same culture, one
species will always outcompete the other.
9. Members of the same species tend to divide resources instead
of competing over them.
Predation, Herbivory, and Keystone Species
Write the letter of the correct answer on the line at the left.
C
10. A lion eating a zebra is an example of
A. herbivory.
C. predation.
B. habitat destruction.
D. a keystone species.
A
11. A cow eating grass is an example of
A. herbivory.
C. habitat destruction.
B. predation.
D. a keystone species.
D
12. A keystone species is one that
A. eats a mixture of plants and animals.
B. is introduced into a community after a major disturbance.
C. causes the amount of diversity in a community to decrease.
D. helps to stabilize the populations of other species in the community.
Symbioses
13. Complete the table about main classes of symbiotic relationships.
Main Classes of Symbiotic Relationships
Class
Description of Relationships
Mutualism (A)
+/+
Commensalism (B)
+/0
Parasitism (C)
+/-
Match the example with the type of relationship. A relationship type may be used
more than once.
Example
C
14.a tick living on the body of a deer
A
15.a bee eating a flower’s nectar and picking up the flower’s pollen
B
16. a barnacle living on a whale’s skin
C
17. a tapeworm living in a person’s intestines
A
18. an aphid providing food to an ant in exchange for protection
4.3 Succession
1. What is ecological succession?
Ecological succession refers to a series of predictable changes that occur in a community
over time.
2. What is primary succession?
Succession that occurs where no soil exists
3. When a disturbance changes a community without removing the soil, what type of
succession follows?
Secondary succession
4. Describe the process of succession in an ecosystem.
Older inhabitants die out and new ones move in (pioneer species  climax
community)
5. Why does secondary succession typically proceed faster than primary succession?
Secondary succession proceeds faster than primary succession because in secondary
succession there is already soil in place, thus a larger range of plant species can colonize
the area.
6. Use the Venn diagram to compare the two types of ecological succession.
Primary
succession
New surface, no
preexisting soil
Both
Become more
complex and
ecologically mature
Secondary
succession
Starts out with
soil in place
Climax Communities
For Questions 8–10, complete each statement by writing the correct word or words.
8. After a natural disaster occurs in a healthy ecosystem, secondary succession will
cause the ecosystem to return to its original climax community.
9. The clearing of a rain forest is the example of a(n) human caused disaster
drastic enough to prevent the original climax community from reforming.
10. During primary succession, chance plays a large role in determining which pioneer
species arrives in an area first.
11. What are the two kinds of disturbances that change ecosystems? Give an
example of each.
The two kinds of disturbances that change ecosystems are natural and human disturbances.
An example of a natural disturbance is a volcanic eruption. An example of a human
disturbance is a farmer clearing a field
4.4 Biomes
For Questions 1–4, complete each statement by writing the correct word or words.
1. The side of a mountain range that faces the wind often receives more rainfall
than the downwind side of the same range.
2. A(n) biome is a group of terrestrial communities that covers a large area and is
characterized by certain soil and climate conditions and particular types of
plants and animals.
3. Organisms within each biome can be characterized by adaptations that enable
them to live and reproduce successfully in the environment.
4. In a tropical rain forest, the layer formed by the leafy tops of tall trees is
called the canopy and the layer of shorter trees and vines is called the
understory.
Complete the table about some of Earth’s major biomes.
Some Major Biomes
Biome
Climate and Soil
Plants and Animals
Tropical
deciduous
forest
warm year-round with wet
and dry seasons; rich soil
plants: tall, deciduous trees; succulents
Tropical rain
forest
Tundra
animals: undergo estivation or migration
Hot and wet nutrient
poor soil
P – broadleaf evergreens and
vines
A – camoflague, use adaptations
for canopy
cold, dark winters and short,
soggy summers; permafrost
plants: ground-hugging plants
Temperate
grassland
Warm to hot summers,
cold winters with
fertile soil
P – grasses and herbs
A – grazing animals
Desert
low precipitation with
variable temperatures
plants: short growth cycles, cacti
animals: birds and mammals that can
tolerate the harsh conditions
animals: adaptations to quickly lose body
heat and regulate body temperature
Boreal forest
Long, cold winters,
mild summers
moderate precipitation
and acidic/poor soil
P – conifers
A – small extremities, insulation
13. Which producers can be found in the polar ice regions?
Algae, moss, lichen
14. Which animals can be found in the northern polar region?
Polar bears, marine mammals, insects, mites
4.5 Aquatic Ecosystems
1.
What are the four main factors that affect aquatic ecosystems?
Depth, temperature, flows, dissolved nutrients
2. What does the depth of the water determine?
Amount of light that can penetrate
3. What distinguishes the photic zone from the aphotic zone in an aquatic
ecosystem?
Sunlight = photic zone
Freshwater Ecosystems
For Questions 4–10, complete each statement by writing the correct word or words.
4. The three main categories of freshwater ecosystems are rivers and streams,
lakes and ponds, and freshwater wetlands
5. Flowing-water ecosystems originate from underground water sources in
mountains or hills.
6. Circulating water in lakes and ponds distributes heat, oxygen and nutrients
throughout the system.
7. Plankton is a general term that includes both phytoplankton and zooplankton.
8. An ecosystem in which water either covers the soil or is present at or near the
surface of the soil is called a(n) wetland.
9. Freshwater wetlands purify water by filtering pollutants.
10. The three types of freshwater wetlands are bogs, marshes, and swamps.
Estuaries
Write the letter of the correct answer on the line at the left.
B
11. Estuaries form where
A. a lake evaporates.
B. a river meets the sea.
C. a river becomes dammed.
D. a wetland becomes filled in.
C
12. The salinity of estuary water is
A. equal to the salinity of river water.
B. less than the salinity of river water.
C. less than the salinity of ocean water.
D. greater than the salinity of ocean water.
C
13. Shallow estuaries allow
A. freshwater wetlands to merge with the estuary.
B. large marine mammals to hibernate in the estuary.
C. sunlight to reach the benthos to power photosynthesis.
D. salt to sink to the bottom of the estuary.
B
14. Temperate estuaries characterized by salt-tolerant grasses above the
low-tide line and seagrasses below water are called
A. bogs.
B. salt marshes.
C. mangrove swamps.
D. freshwater wetlands
Marine Ecosystems
15. Complete the diagram by adding labels for each marine zone. Then shade in the aphotic zone.
Intertidal zone
Coastal ocean
Benthic zone
Open ocean
Aphotic zone =
everything under the
200m mark.
16. Complete the table about the type of organisms living in each ocean zone.
Marine Life by Ocean Zone
Zone
Life Forms
COASTAL
kelp forests, coral reefs
INTERTIDAL
barnacles, seaweed, starfish
OPEN OCEAN
large marine mammals such as whales, chemosynthetic bacteria
Chapter Vocabulary Review
Match the term with its definition
Term
Definition
A. the average yearly condition of temperature and
precipitation in a region
B. the full range of conditions in which an organism
lives and the way in which the organism uses those
conditions
F
1. Weather
C
2. greenhouse effect
B
3. niche
E
4. predation
C. natural situation in which atmospheric gases trap
heat inside Earth’s atmosphere
A
5. climate
D. permanently frozen subsoil
H
6. herbivory
G
7. humus
E. interaction in which an organism captures and feeds
on another organism
D
8. permafrost
F. day-to-day condition of Earth’s atmosphere at a
particular time and place
G. a material formed from decaying leaves and other
organic matter
H. interaction in which an organism feeds on a primary
producer
Complete each statement by writing the correct word or words.
9. The three main types of symbiotic relationships in nature are
MUTUALISM, PARASITISM, AND COMMENSALISM
10. The gradual change in living communities that follows a
disturbance is called .ECOLOGICAL SUCCESSION
11. The first species to live in an area of primary succession are called PIONEER
SPECIES.
12. The area where an organism lives is its HABITAT.
13. The ability of organisms to survive and reproduce under a range of
environmental circumstances is called TOLERANCE
14. The TAIGA (BOREAL FOREST) contains dense evergreen forests of
coniferous trees.
15. The well-lit upper layer of ocean water is known as the PHOTIC ZONE.
16. The tiny, free-floating, weakly swimming algae and animals that occur in both
freshwater and saltwater environments are called PLANKTON
17. Organisms that live on the ocean floor are referred to as BENTHOS