Download unit 5: the interdependence of organisms

UNIT 5: THE INTERDEPENDENCE OF ORGANISMS
Benchmark 1.13 (SOL-BIO1 and BIO9)
Students investigate and understand that the atoms and molecules on Earth cycle among the living and
nonliving
components of the biosphere.
Indicators
1.13.1 Illustrate the interdependence of living things using the concepts of matter and nutrient cycling.
1.13.2 Explain how photosynthesis and cellular respiration are complementary processes for cycling
carbon
dioxide and oxygen within an ecosystem.
Benchmark 1.14 (SOL-BIO1 and BIO9)
Students investigate and understand that energy flows through ecosystems in one direction, from
photosynthetic
organisms to herbivores, to carnivores, and to decomposers.
Indicators
1.14.1 Illustrate the interaction of producers and consumers in an ecosystem with food chains, food
webs, and
energy pyramids.
1.14.2 Explain how photosynthesis and cellular respiration are complementary processes for the
transformation of energy within an ecosystem.
Benchmark 1.15 (SOL-BIO1, BIO5, BIO7, and BIO9)
Students investigate and understand that organisms both cooperate and compete in ecosystems. The
interrelationships and interdependence of these organisms may generate ecosystems that are stable for
hundreds
or thousands of years.
Indicators
1.15.1 Relate the concepts of individuals, populations, communities, and ecosystems to each other.
1.15.2 Illustrate the interactions within and among populations, including carrying capacities, limiting
factors,
and growth curves.
1.15.3 Cite several examples of predation, parasitism, commensalism, mutualism, and competition.
1.15.4 Compare biotic and abiotic features of various terrestrial and aquatic biomes.
1.15.5 Illustrate the various succession patterns in ecosystems.
Benchmark 1.16 (SOL-BIO1, BIO5, BIO8, and BIO9)
Students investigate and understand that human beings live within the world's ecosystems. Increasingly,
humans
modify ecosystems as a result of population growth, technology, and consumption. Human destruction of
habitats
by direct harvesting, pollution, atmospheric changes, and other factors may threaten global stability and
could
result in irreversible damage to ecosystems.
Indicators
1.16.1 Formulate ways of dealing with environmental problems such as air pollution and
overpopulation.
----------------------------Associated Laboratory Activities
Students should complete activities which enable them to:
5a. Understand the effects of population growth in relation to the ecosystem.
5b. Understand how energy passes from one trophic level to another as it moves through the ecosystem.
Glencoe
Text p. 86 Mini Lab How Can
You Create a Closed
Ecosystem?
Text p. 150 Biolab Degrading
Time of Packing Material
LM p. 129 INV 23-2 Which
Foods Can Bread Mold Use
for Nutrition?
Text p. 66 Biolab How Can
One Population Affect
Another?
Text p. 116 Biolab Population
Growth in Paramecium
LM p. 15 INV 3-2 The Lesson
of the Kaibab.
5a Effects of
Population Growth
Endangered Species :
Population Bottlenecks in
Mauna Kea Silversword Book 1
p. 73
Population Sampling : A
Simulated Field Study Book 1 p.
115
Exp. 21 Physical Profile of a Lake p. 21-1
Exp. 13 Population Dynamics p. 13-1
Exp. 18 Acid Rain p. 18-1
Ecology
First Look
Explorations: Introduction; Observing
Population Growth; Modifying Population
Growth; Two Populations: What's the
Difference?; Two Competing Populations;
Enter Predator; Maintaining a Balance
Core Inquiries: S and J Curves; Introducing
a Virus; Effect of Food Supply; Carrying
Capacity and Grass; Competition; Changing
Environmental Conditions; Predation; Eating
Efficiently; Survival Strategies;
Environmental Changes; Maintaining
System Balance; Competition Pressure
Independent Investigations: Design an
Animal; Design an Ecosystem; Global
Warming
5b Energy Flow
Within
Ecosystems
Counting and Coverage: A
Simulated Field Study Over
Time Book 1 p. 63
Exp. 14 Interdependence of Plants and
Animals p. 14-1
Exp. 19 Dissolved Oxygen in Water p. 19-1
Exp. 20 Watershed Testing p. 20-1
Exp. 22 Five - Day BOD p. 22-1
Exp. 25 Primary Productivity p. 25-1
Relevant Virginia Standards of Learning (SOL)
BIO.8 The student will investigate and understand how
populations change through time. Key concepts include
* examining evidence found in fossil records;
* investigating how variation of traits, reproductive
strategies, and environmental pressures impact on the
survival of populations;
* recognizing how adaptations lead to natural selection; and
* exploring how new species emerge.
BIO.9 The student will investigate and understand dynamic
equilibria within populations, communities, and
ecosystems. Key concepts include
* interactions within and among populations including
carrying capacities, limiting factors, and growth curves;
* nutrient cycling with energy flow through ecosystems;
* succession patterns in ecosystems;
* the effects of natural events and human influences on
ecosystems; and
 analysis of local ecosystems.
Relevant Virginia SOL Review Questions
1. The study of how living things relate to each other and to their environment is called:
a. ecology *
b. mutualism
c. food web
d. commensalism
2. A relationship between two organisms in which both benefit is called:
a. commensalism
b. mutualism *
c. autotrophism
d. parasitism
3. A network of interconnected food chains is called a:
a. decomposer
b. food web *
c. biosphere
d. food chain
4. A relationship between two organisms in which one benefits and the other neither benefits nor is harmed
is
called:
a. mutualism
b. parasitism
c. decomposer
d. commensalism *
5. The layer of Earth that supports life is:
a. ecology
b. the habitat
c. the biosphere *
d. trophic levels
6. An organism that feeds on dead organisms is a:
a. scavenger *
b. parasite
c. herbivore
d. plant
7. A simple model for showing how matter and energy move through the ecosystem is a:
a. trophic level *
b. food web
c. habitat
d. food chain
8. An organism that manufactures food using energy from the sun or from chemical compounds is a:
a. heterotroph
b. decomposer
c. autotroph *
d. parasite
9. The role an organism has in the environment is called:
a. ecology
b. the biosphere
c. a habitat
d. a niche *
10. An organism that obtains energy from breaking down dead organisms is called a:
a. parasite
b. autotroph
c. carnivore
d. decomposer *
11. Which is not recycled in the biosphere?
a. water
b. energy *
c. oxygen
d. all of these are recycled
12. The largest biome is the:
a. tundra
b. coniferous forest
c. desert
d. ocean *
13. The greenhouse effect is due to a buildup of:
a. nitrates
b. water vapor
c. carbon monoxide
d. carbon dioxide *
14. A prey population usually decreases as the predator population:
a. increases *
b. decreases
c. immigrates
d. stays the same
15. All the possible food chains in a habitat are called:
a. a niche
b. a food web *
c. a trophic level
d. a community
16. Limiting factors keep populations from:
a. declining
b. emigrating
c. getting too large *
d. getting too small
17. Which of the following shows the correct order of a food chain?
a. primary consumer-> producer-> secondary consumer
b. secondary consumer-> producer-> primary consumer
c. producer-> primary consumer-> secondary consumer *
d. producer-> secondary consumer-> primary consumer
18. Which type of organism is not shown in the following representation of a food chain? grass--> mouse->
snake--> hawk
a. herbivore
b. decomposer *
c. producer
d. carnivore
19. Phytoplankton --> Zooplankton --> Mussels --> Starfish
What effect would harvesting the mussels have on this food chain?
a. The carbon dioxide levels in the water would decrease.
b. The oxygen levels in the water would decrease.
c. The starfish population would increase.
d. The zooplankton population would increase. *
20. Aerobic organisms are dependent on autotrophs. One reason for this dependency is that most autotrophs
provide the aerobic organisms with:
a. oxygen *
b. carbon dioxide
c. nitrogen gas
d. hydrogen
21.The pictures show the results of allowing bread mold in a sealed jar for a week. Which of these best
explains the
lack of change in mass in this demonstration?
a. Water evaporated from the bread at the same rate mold grew on it.
b. Materials are recycled in closed environmental systems. *
c. Populations in closed systems grow until the food supply is gone.
d. Some of the mold is dying.
Organisms, Ecosystems, and Population Growth: Interrelationsips
and Interdependencies
NSES Generalization
Organisms both cooperate and compete in ecosystems. The interrelationships and interdependencies of
these
organisms may generate ecosystems that are stable for hundreds or thousands of years.
Living organisms have the capacity to produce populations of infinite size, but environments and
resources
are finite. This fundamental tension has profound effects on the interactions between organisms.
Human beings live within the world’s ecosystems. Increasingly, humans modify ecosystems as a result
of
population growth, technology, and consumption. Human destruction of habitats through direct
harvesting,
pollution, atmospheric changes, and other factors is threatening current global stability, and if not
addressed,
ecosystems will be irreversibly damaged.
Further Description
The organization of ecosystems is based upon populations interacting with each other and with abiotic
factors of the environment. The interaction of populations sets up a community. Populations may
interact in
positive or negative ways. An example of a positive interaction is seen in the pollinating activities of
flowering plants. In this symbiosis, the flower is fertilized while the pollinator collects its food.
Predator-prey relationships show a positive as well as negative association. Competition for resources
can
also cause negative interaction. In this case the population most affected by the competition is
eliminated
from a niche. Because of these interactions, numerous adaptations have evolved that prevent elimination
of
populations from a selected ecosystem. Species have adapted to be able to coexist with each other by
sharing resources, reducing competition, and entering into positive symbioses.
In any community, populations will tend to replace each other in an orderly process. This is due to the
fact
that habitat populations change. Use of nutrients and other "abiotic" factors by resident populations
causes
habitats to change, resulting in a replacement process, or succession. This process of community change
results in a
series of transitory communities until a final or mature community is established. Given sufficient time
and stability of
biotic and abiotic factors, a climax will be reached. The climax community can last for hundreds of
years
uninterrupted.
All populations have an inherent tendency to increase in size. This potential increase is extremely high
for most
species. This type of exponential growth begins slowly and then continues on a rapid incline as more
reproductive
individuals are produced each generation. Control of population growth is based upon limiting factors
and population
interactions in each ecosystem. Resources such as food, water, oxygen, and space availability, as well as
predation,
competition, and parasitism, place environmental limits on population growth. These limits set the
carrying capacity of
the ecosystem. Population size will oscillate around this carrying capacity. When a population exceeds
carrying
capacity, a strain upon resources could result in a sharp decline in the population.
Human civilization has brought about dramatic changes in the ecosystems of the world. These changes
have resulted
in major environmental problems, which in turn directly affect the survival of all species on Earth.
Because of
agricultural practices, technological advances, and medical triumphs, world population growth has
reached a size well
over 5 billion. This "population explosion," coupled with a lack of understanding of ecological
principles, has
resulted in massive pollution of land and water, destruction of habitats and loss of bio-diversity, possible
climate changes that could result in global warming, and penetration of the protective ozone layer
shielding all
life from harmful UV rays. Policy decisions facing planet Earth should focus on population control,
recycling of
human waste, and development of alternative energy sources, and should develop a better understanding
of the
human impact on ecosystem balance.
Concepts Needed
Grade 9
Population, community, niche, habitat, competition, ecosystem, limiting factors, exponential growth
mortality
Grade 10
Succession, serial stages, ecotone, pioneer species, climax communities, associations, community
Grade 11
Symbiosis, predator-prey, mutualism, amensalism, commensalism, parasitism, succession, biotic
potential,
agriculture, technology, human population growth form, biodiversity, layers of the atmosphere, waste
disposal,
fossil fuels, recycling, pesticides, pollutants, endangered species, abiotic factors
Grade 12
Density-dependent and density-independent factors, carrying capacity, acid rain, ozone depletion,
succession,
climax concept
Empirical Laws or Observed Relationships
Interdependence, population levels of species fluctuate with environmental conditions
Theories or Models
Competitive exclusion principle, equilibrium hypothesis of island biogeography, climax communities,
facilitation
hypothesis, inhibition hypothesis, J-shaped and S-shaped growth form, age distribution pyramids, r and
K
strategies, global warming, succession
Cycles in the biosphere and Energy Flow through Ecosystems
NSES Generalization
The atoms and molecules on the earth cycle among the living and nonliving components of the
biosphere.
Energy flows through ecosystems in one direction, from photosynthetic organisms to herbivores to
carnivores
and decomposers.
Further Description
The cycling of nutrients in any ecosystem is essential to maintain a balance in that ecosystem.
Ecosystems
are dependent upon resources that are used by organisms and the recycling of wastes disposed by them.
Essentially the same atoms and molecules are being used over and over again. Nutrient cycling of
organic
and inorganic substances takes place in all ecosystems. Nutrients critical for maintaining homeostasis in
any ecosystem are carbon, nitrogen, and phosphorus.
The carbon cycle begins with atmospheric CO2 , which is absorbed by plants. CO2 is fixed through
photosynthesis into glucose, which is used by all organisms in respiration to produce ATP. In
respiration,
CO2 is released as a waste product and sent back to the atmosphere. This cycle sets up the basic food
chain
for all ecosystems. CO2 is released into the atmosphere through decomposition and combustion as well,
adding to the reservoir of CO2 necessary to continue this cycle.
The nitrogen cycle is based upon the action of the decomposers in soil. Decomposers have the ability to
convert nitrogen wastes and dead organic matter into a usable form for plants. In addition, a special
group
of nitrogen-fixing bacteria can convert nitrogen gas from the atmosphere into nitrates.
The phosphorous cycle is a sedimentary cycle; that is, rock containing small amounts of phosphorous is
eroded and phosphorous then becomes available to plants. Animals take in phosphorous from the food
web, use it in making ATP and DNA, and through excretion, release it as a waste. Bound-up
phosphorous is
released into the soil by decomposers.
Water, essential for all life, must also be cycled. The cycling of water occurs through evaporation,
condensation, and precipitation. The sun causes evaporation from the oceans and lakes as well as
transpiration from plants. Water is carried to the atmosphere condensed and falls in the form of rain or
snow. The amount of precipitation helps define the type of ecosystem that will exist in a particular
geographic region.
The fuel for ecosystems is the sun’s energy. This radiant energy is captured by plants and converted into
a
usable form of chemical energy, namely glucose. Energy flow in ecosystems occurs when the primary
producers (plants) carrying this energy are eaten by herbivores (animals that eat only plants), which in
turn
are eaten by carnivores (animals that eat only animals). This sets up what is known as a food chain.
Food
chains, however, are usually rare. In most ecosystems food chains usually become food webs. A web
occurs when one or more levels of the food chain interconnect with other levels for their food supply.
Food
webs are usually complex and can define niche adaptations in ecosystems.
Concepts Needed
Grade 9
Biotic, abiotic, biosphere, natural resources, organic compound and inorganic compound,
decomposition,
condensation, precipitation, microorganisms, photosynthesis, carbon cycles, energy flow, producers,
consumers, herbivores, carnivores, omnivores, food chains, food webs, habitat, niche, decomposers
Grade 10
Predator-prey dynamics, carbon cycle, ecosystem, trophic structure
Grade 11
Phosphorous cycle, carbon cycle, nitrogen cycle, human waste disposal and fossil fuel consumption
Grade 12
Decomposers, trophic levels, heat budgets, energetics
Empirical Laws or Observed Relationships
Conservation of matter, first and second laws of thermodynamics
Theories or Models
Trophic pyramids, food web, hydrologic cycle, carbon cycle, nitrogen cycle, phosphorous cycle