CP Biology
2015-2016
Name
______
____________
UNIT 2C: Chemistry of Ecology
Chapter 3.4: Cycles of Matter
What four elements primarily make up living organisms?
These elements (along with others such as sulfur and phosphorus)
are the basis of life’s most important compounds:
 Water
 Carbohydrates
 Lipids
 Nucleic Acids
 Proteins
_Carbon, Hydrogen, Oxygen and Nitrogen_____
Nutrients are recycled through biogeochemical cycles.
These cycles are powered by the one-way flow of energy
through the biosphere.
In other words, a handful of elements combine to form the building
blocks of all known organisms – however, organisms cannot
manufacture these elements and do not ‘use them up’ – you may
wonder where these essential elements come from and how their
availability affects ecosystems.
Water is energy,
Wheel is the cycle
of matter
Although energy in the form of sunlight is constantly entering the
biosphere, Earth doesn’t receive a significant, steady supply of new
matter from space. Unlike the one-way flow of energy, matter is
recycled within and between ecosystems.
Your personal notes, summary of the lesson, and/or questions that you may have:
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Biogeochemical cycle: process in which elements, chemical
compounds, and other forms of matter are passed from one organism
to another and from one part of the biosphere to another.
As matter moves through these cycles, it is transformed which
means that it is never created or destroyed, just changed.
There are many ways in which the processes involved in
biogeochemical cycles can be classified:

Biological Processes: any and all activities performed by
living organisms ex) eating, breathing, burning food,
eliminating waste

Geological Processes: volcanic eruptions, formation &
breakdown of rock, major movements of matter within and
below the surface of the earth.

Chemical and Physical Processes: formation of clouds &
precipitation, flow of running water, lightning

Human Activity: mining, burning of fossil fuels, clearing of
land for building and farming, burning of forests, manufacture
& use of fertilizers
These processes pass the same atoms and molecules around again and
again.
Your personal notes, summary of the lesson, and/or questions that you may have:
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The Water Cycle
Water continuously moves between the oceans, the
atmosphere and the land - sometimes outside living
organisms and sometimes inside them.
Water (H2O) is one of the few substances that occurs commonly in all
three states (solid, liquid, gas) on Earth.
How does water vapor (gas) enter the atmosphere?
 Evaporation: water turns to a gas by evaporating from the
ocean or other bodies of water (liquid  gas)
 Transpiration: water turns to a gas by evaporating from the
leaves of plants ( = plant sweat)
 Combustion: burning of fuels – produces water (and carbon
dioxide)

Respiration: cellular respiration by all organisms produces
water (and carbon dioxide) (remember: all organisms
undergo CR!)
Once water vapor is in the atmosphere, winds can transport it over
great distances.
Your personal notes, summary of the lesson, and/or questions that you may have:
The SUN is the driving force of the water cycle!!!
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The Water Cycle Continued…

Condensation: When water vapor cools, the vapor condenses
into tiny droplets (liquid) that form clouds. (gas  liquid)

Precipitation: When the droplets of water in clouds become
large enough, they fall to Earth’s surface as precipitation in
the form of rain, snow, sleet, or hail

Runoff: On land, some precipitation flows along the surface
in what is called ‘runoff’, until it enters a river or stream that
carries it to an ocean or lake.

Groundwater: Precipitation can also be absorbed into the soil
and then it is called groundwater which can enter plants
through their roots, or flow into rivers, streams, lakes or
oceans. Some can even become part of underground
reservoir (aquaphors – fresh underground water source)
Using the Word Bank, fill in the blank spots of the Water Cycle:
Your personal notes, summary of the lesson, and/or questions that you may have:
The SUN is the driving force of the water cycle!!!
http://www.hhmi.org/biointeractive/gorongosas-water-cycle
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Nutrient Cycles
Nutrients: the chemical substances that an organism needs to sustain
life
Like water, nutrients pass through organisms and the environment
through biogeochemical cycles. Three of these that are especially
critical for life are the cycles that move carbon, nitrogen and
phosphorous through the biosphere.
The Carbon Cycle
Carbon is a major component of all organic compounds. It is also
important in some inorganic compounds such as calcium carbonate
(formula: CaCO3) that is part of different kinds of animal skeletons
and carbon dioxide (formula: CO2) which is a major part of the
atmosphere and is necessary for photosynthesis.
Carbon dioxide is continuously exchanged between the atmosphere
and oceans through chemical and physical processes.
Fossil Fuels: Some carbon-containing compounds that were once
part of ancient forests, marine organisms, or other animals have been
buried and transformed into energy-rich fuels such as coal, oil, and
natural gas.
Major reservoirs of carbon in the biosphere include the:
 Atmosphere - as CO2 gas
 Oceans - as dissolved CO2 (gas in water)
 Rocks - as CaCO3 (calcium carbonate)
 Fossil Fuels - coal, oil, natural gas
 Forests - found in plants
Why does every organism need nutrients?
_To carry out life processes (i.e., reproduction, growth,
homeostasis). The nutrients provide the building blocks to
accomplish these processes.
What is the role of oxygen in the common biogeochemical cycles on
Earth?
It combines with other elements (i.e., carbon) and cycles through
many biogeochemical processes. It is a product of photosynthesis
and a reactant for cellular respiration (combustion).
What role do you think decomposers play in the cycling of carbon
and oxygen in the biosphere?
_Decomposers unlock the carbon in wastes and dead organisms.
Also, decomposers (as consumers) use oxygen and produce
carbon dioxide as a waste product.
Fill in the blanks!
Carbohydrates
Decomposers
Photosynthesis
Respiration

Plants take in CO2 during _photosynthesis______ and use the
carbon to build macromolecules like _carbohydrates__ .
These nutrients then pass through food webs to consumers.

Organisms release carbon in the form of CO2 gas by _cellular
respiration

When organisms die__decomposers_____ break down the
bodies, releasing carbon to the environment.
Your personal notes, summary of the lesson, and/or questions that you may have:
Producers are the driving force of the Carbon/Oxygen Cycle!!!!!!!!!!
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The Nitrogen Cycle
All organisms require nitrogen to build amino acids and nucleic
acids so that organisms can build DNA, RNA and proteins.
Many different forms of nitrogen occur naturally in the biosphere.
 Nitrogen gas (N2) makes up 78% of earth’s atmosphere.
 Ammonia (NH3), nitrate ions (NO3), nitrite ions (NO2) are
found in soil, in the wastes produced by many organisms,
and in dead and decaying organic matter.
 Dissolved nitrogen exists in several forms in the ocean and
other large water bodies
Although nitrogen gas is the most abundant form of nitrogen on
Earth, only a handful of organisms – certain types of bacteria – can
use this form directly. Because they “lock” (=fix) the nitrogen into
usable forms, these nitrogen-fixing bacteria are an essential part of
the nitrogen cycle.
How do decomposers release nitrogen from waste and dead organisms
into the atmosphere?
_Decomposers release nitrogen into the soil in the form of
ammonia, nitrites, and nitrates for the producers to take up.___
What is the process of detnitrification?
_Certain types of bacteria (not the nitrogen fixers) obtain energy
by converting nitrates back into nitrogen gas
Note: lightning can also accomplish this process (not a big source
of usable nitrogen).
What is the process of Nitrogen Fixation?
_Nitrogen fixing bacteria can take N2 gas from the atmosphere
and convert it in ammonia, nitrates, and nitrites (that other
organisms can utilize).
How do humans add EXCESS nitrogen to the biosphere?
__by the manufacture and use of fertilizers on crops and lawns.__
Nitrogen Fixation: In this process, certain types of bacteria convert
Nitrogen Gas into Ammonia, Nitrates, and Nitrites. Some of these
bacteria live in the soil whereas others live on the roots of certain
plants called legumes (ex. peanuts, peas, soybeans).
Once these forms of nitrogen are available, primary producers can
use them to make proteins and nucleic acids.
Consumers eat the producers and reuse nitrogen to make their own
nitrogen-containing compounds.
Decomposers will return the nitrogen from organisms back to
the soil.
Denitrifying bacteria return nitrogen from soil to atmosphere!
Your personal notes, summary of the lesson, and/or questions that you may have:
BACTERIA drive the nitrogen cycle!!!
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Chapter 4: Ecosystems and Communities
4.2 – Niches and Community Interactions
Niche: describes not only what an organism does, but also how it
interacts with biotic and abiotic factors in the environment.
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.
 Resources and the niche resource is any necessity of life such
as nutrients, light, food or space
 Physical Aspects of the Niche: an organism’s niche involves
the abiotic factors it requires for survival such as water, temp,
light
 Biological Aspects of the Niche an organism’s niche involves
certain biotic factors required for survival such as
reproduction, food-getting
Competition
Competition occurs when organisms attempt to use the same limited
ecological niche in the same place at the same time.
Competitive Exclusion Principle: states that no two species can
occupy exactly the same niche in exactly the same habitat at exactly
the same time.
Predator-Prey Relationships
What is the result if two species do attempt to occupy the same
niche?
__*one species will be better at competing for limited resources and
will eventually exclude the other species.________________
Instead of competing for similar resources, species usually divide
them. Give an example of this:
_ three species of North American warblers all live in the same trees
and eat insects, but feed on different types of insects in different
sections of the tree. Some species come out at different times of the
day/night.
________________
called Resource or Niche Partitioning
By causing species to divide resources,__competition___________
helps determine the number and kinds of species in a community and
the niche each species occupies.
Give an example of a predator-prey relationship that you may see in
your own local ecosystem.
_______ Ex. hawks eat mice _______
_______________________________________________________
_______________________________________________________
Predation: an interaction in which one animal (the predator) captures
and feeds on another animal (the prey)

Predators can affect the size of prey populations in a
community and determine the places prey can live and feed.
Your personal notes, summary of the lesson, and/or questions that you may have:
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Herbivore-Plant Relationships
Herbivory: an interaction in which one animal (the herbivore) feeds
on producers (such as plants)

Herbivores can affect both the size and distribution of plant
populations in a community and determine the places that
certain plants can survive and grow.
Keystone Species: a single species that is not usually abundant in a
community yet exerts strong control on the structure of a community
SYMBIOSES
Symbiosis: any long term relationship in which two species live
closely together and are dependent upon each other
Three main types of symbiotic relationships in nature:
1. Mutualism: symbiotic relationship in which both species
benefit from the relationship (+/+)
2. Parasitism: a symbiotic relationship in which one organism
lives inside or on another organism and harms it by obtaining
all or part of its nutritional needs from the host organism. (+/-)
3. Commensalism: symbiotic relationship in which one
organism benefits and the other is neither helped nor harmed.
(+/0)
Give an example of herbivory you may see in your own local
ecosystem.
__deer and plants_________________________
_______________________________________________________
_______________________________________________________
Describe the dramatic effects that the dam-building activities of
beavers (a keystone species) might have on other types of organisms.
__by building a dam, it floods the area behind the dam and
creates a brand new ecosystem where an abundance of new
species can occupy (they may not have been able to occupy
without the beaver’s dam)_____________________________
Symbioses – Circle which species benefits from the relationship and
which species is harmed, if any.
1. Mutualism –
a. Who benefits? One Species Both Neither
b. Who is harmed? One Species Both Neither
Example(s): _clownfish and sea anemone (bee and flower)
2. Parasitism –
a. Who benefits? One Species Both Neither
b. Who is harmed? One Species Both Neither
Example(s): _tick and a deer; mosquito and organism
3. Commensalism –
a. Who benefits? One Species Both Neither
b. Who is harmed? One Species Both Neither
Example(s): barnacles and a whale; hermit crabs and snail
shells__
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