Honors Biology
Name
Chemistry of Ecology (Part A)
Ecology _______________________________________________________________
3.1 What is Ecology
There is interdependence between organisms and the environments in which they live. Organisms respond
to their environment and can also change their environments, therefore the biosphere is dynamic.
Ecological Levels of Organization
There are 6 ecological levels of organization presented in circular representations on pages 64-65 of your
textbook. Start on the bottom left of page 64 and count #1-6 as you move to the right side of page 65.
1._____________________________________________________________________________
2. _____________________________________________________________________________
3. _____________________________________________________________________________
4. _____________________________________________________________________________
5. _____________________________________________________________________________
6. _____________________________________________________________________________
What is the difference between an organism and a species?
________________________________________________________________________
________________________________________________________________________
What is the difference between a population and a community?
________________________________________________________________________
________________________________________________________________________
What is the difference between a community and ecosystem?
________________________________________________________________________
How are the terms ecosystems and biomes related?
________________________________________________________________________
________________________________________________________________________
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The biosphere consists of all areas on Earth in which life exits, including _____________(lithosphere),
_____________(hydrosphere), and ______________.
The word environment refers to all conditions or factors surrounding an organism. These factors can be living
or nonliving.
Any living part of the environment with which an organism might interact is known as a
_______________factor, while the physical (nonliving) parts of ecosystems are called
______________factors.
Which of the 6 levels of organization include abiotic factors?
_______________________________________________________________________
Fill in the
Blanks
In the
Diagram.
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Chapter 3: The Biosphere
3.2 – Energy, Producers and Consumers
At the core of every organism’s interaction with the environment is its need for ____________ to power
life’s processes. You may wonder where energy in living systems comes from and how it is transferred
from one organism to another.
Materials and energy move between the living (biotic) and nonliving (abiotic) parts of
ecosystems. Materials (atoms, molecules) must be recycled but energy is NOT - therefore a
constant supply of energy must enter every ecosystem (usually from the sun).
Organisms must be able to: a) produce or obtain nutrients; b) convert the nutrients into usable forms of
chemical energy (making ATP through cellular respiration); and c) use these forms of energy to power their
life processes.
For most life on earth, the ______________ is the ultimate energy source.
There are different types of autotrophy: ____________________ and _____________________, which
differ in terms of the energy they harness (solar or chemical) to produce carbohydrates.
Autotroph:
Autotrophs are also called ______________ ________________ because they are they store energy in
forms that make it available to other organisms that eat them. So, they are the first producers of energy-rich
compounds that are later used by other organisms.
Autotrophs are essential for the flow of energy through the biosphere because they are the first producers
of energy-rich ____________________ that are later used by other organisms.
Photosynthesis:
Examples of photosynthetic organisms:
Chemosynthesis
Examples of chemosynthetic organisms:
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Heterotroph:
Heterotrophs are also called _________________ because they rely on other organisms for energy and
nutrients and cannot produce it for themselves. There are a variety of ways that consumers can acquire
energy and nutrients.
There are 6 categories of consumers listed in your book on page 71. Use the diagrams and descriptions
provided to fill in the information below. Write in your own words!
1. Carnivores__________________________________________________________________
Examples include: _______________________________________________________
2. Scavengers________________________________________________________________
Examples include: _______________________________________________________
3.Decomposers__________________________________________________________________
Examples include: _______________________________________________________
4.Herbivores___________________________________________________________________
Examples include: _______________________________________________________
5.Omnivores____________________________________________________________________
Examples include: _______________________________________________________
6.Detrivores___________________________________________________________________
Examples include: ______________________________________________________
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3.3 – Energy Flow in Ecosystems
In every ecosystem, primary producers and consumers are linked through _______________ relationships.
Though there is a wide variety of feeding relationships in various ecosystems, energy flows through an
ecosystem in a ________-_________ stream, from primary producers to various consumers.
The ultimate source of energy is the sun and energy flows through ecosystems in a one-way stream
from producers to various levels of consumers.
A _____________ ______________ is a series of steps in which organisms transfer energy by eating and
being eaten. Food chains vary in length, or in the number of steps depending on the specific ecosystem.
Feeding relationships are complicated and don’t occur as simple isolated
food chains. ______________ _______________ consist of interconnected food chains, and show
networks of feeding interactions.
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What is the difference between a food chain and a food web?
What is the importance of decomposers and detritivores in a food web?
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*We will complete this flow chart together in class*
Trophic Level:
Which trophic level always includes primary producers?
Which type of organisms occupy all the other trophic levels?
_____________________ _______________________show the relative amounts of energy or biomass (in
terms of living matter or numbers of individuals) contained in each trophic level in a given food chain or
food web.
What are the three types of ecological pyramids?
A Pyramid of Energy shows:
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Energy is lost due to :
a) *_______________________________________________________________________________
b) *_______________________________________________________________________________
c) *_______________________________________________________________________________
On average, about _______ percent of the energy available within one trophic level is transferred to the
next trophic level.
THINK!! The diagram shows that a large amount of energy is released from each step as “heat”. Which
essential metabolic process creates this heat?
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Gross vs. Net Productivity
*
: all the energy (glucose) the plant ever produced from sunlight
*
: gross primary productivity minus all energy used in cellular
respiration and eventually heat. This is what is available to the next trophic level. Also known as biomass
(all organic compounds minus water)
A Pyramid of Biomass shows:
Biomass:
Biomass is usually measured in
The amount of biomass a given trophic level can support is
determined, in part, by the amount of ________________
available.
A Pyramid of Numbers shows:
In most ecosystems, the shape of the pyramid of numbers is similar to the shape of the pyramid of biomass
for the same ecosystem. In this shape, the numbers of individuals on each level ________________ from
the level below it.
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Describe an example in which a pyramid of numbers may be turned upside whereas
the corresponding pyramid of biomass would have the normal orientation.
Chapter 4: Ecosystems and Communities
4.2 – Niches and Community Interactions
Niche:
Niche refers to the range of physical and biological conditions in which a species lives and way species
obtain what they need to survive and reproduce. Niche describes where an organism lives, what it does, and
how it interacts with biotic and abiotic factors in the environment. Niche refers to an organisms total way of
life.
Define the following terms:
Tolerance:_______________________________________________________________________
________________________________________________________________________
Habitat:_______________________________________________________________________
________________________________________________________________________
Resource: _______________________________________________________________________
________________________________________________________________________
How is a niche like a profession? In ecological terms, describe your niche and be sure to include resources,
physical, and biological aspects of your niche.
Competition
Competition occurs when organisms attempt to use the same limited ecological
_______________ in the same ______________ at the same ____________.
What is the difference between intraspecific competition and interspecific
competition?*
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Competitive Exclusion Principle:
What is the result if two species do attempt to occupy the same
niche?
Instead of competing for similar resources, species usually
them. Give an example of this:
Therefore competition helps determine the number and kinds of species in a community and the niche each
species occupies.
Predator-Prey Relationships
Predation:
Predators can affect the ___________ of prey populations in a community and
determine the places prey can ____________ and ____________.
THINK! Give an example of a predator-prey relationship that you may see in your own local ecosystem.
Using the above diagram, why do the oscillations of the lynx population follow those of the hare
population? *
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Herbivore-Plant Relationships
Herbivory:
Herbivores can affect both the ____________ and ________________ of
plant populations in a community and determine the places that certain
plants can ____________and ________.
THINK! Give an example of herbivory you may see in your own local ecosystem.
SYMBIOSES
Symbiosis:
Three main types of symbiotic relationships in nature:
1) Mutualism:
Who benefits?
Example(s):
Who is harmed?
*ex) Lichens:
2) Parasitism:
Who benefits?
Who is harmed?
Example(s):
3) Commensalism:
Who benefits?
Who is harmed?
Example(s):
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