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Name: _____________________
Date: __________
Unit 2 Ecological Biochemistry
2C Chemistry of Ecology
NOTES
Food and Nutrition
Food (__________________________) is needed for your cells to produce ATP
(___________________ energy).
- Also supplies raw materials for your body to build and repair.
Energy:
When food is burned, most energy is released as________________, which is
measured in calories.
Energy in food molecules is released during _______________________________
and used to produce ______________ to power cellular activities.
Raw materials:
Energy can be extracted from almost any type of food.
So why does it matter which foods you eat?
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
Examples of molecules made from raw food materials: enzymes, lipids in cell
membranes, DNA
A healthy diet provides all of the necessary raw materials your body needs.
Additional Notes/Summary:
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Nutrients- molecules (matter) ingested from the environment that are needed for
__________________________________
Nutrients your body needs include: water, carbohydrates, fats, proteins,
vitamins, and minerals.
Carbohydrate Use and Storage:
Carbs are the main source of energy for the body
 Simple Sugars (mono and disaccharides)
o Fruits, honey, sugar cane
o Used ______________ for energy
 Complex Sugars (polysaccharides)
o Grains, potatoes, vegetables
o ____________________ into simple sugars to the be used for
energy
 In animals, excess blood sugar is converted into glycogen which is stored
in the _____________and ______________________________.
o __________________ excess sugar can also be converted to and
stored as body fat
A balanced diet provides nutrients in adequate amounts
and enough energy for a person to maintain a healthful
weight.
If you undergo prolonged starvation, what order will you use
the following organic compounds to obtain energy?
Choices: glucose, ATP, proteins, fats, complex
carbs
______________→ ______________→ _______________ →_____________→
_______________
Why are proteins broken down last? _____________________________________
__________________________________________________________________
Additional Notes/Summary:
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Cycles of Matter
The four main elements of living things that help make up:





Water
Carbohydrates
Lipids
Nucleic Acids
Proteins
Energy flows in a _____________________ direction starting from the sun
Matter is ___________________ throughout the biosphere
Matter is Recycled Within and Between Ecosystems
 This is different than the one-way flow of energy through an ecosystem
Biogeochemical cycle: process in which elements, chemical compounds (water
and nutrients), and other forms of matter are passed from one organism to another
and from one part of the biosphere to another.
- Can be biological, geological, chemical, physical, or from human activity
THINK! Give an example of a process in each of the following categories:
Biological- _________________________________________________________
Geological- ________________________________________________________
Chemical- formation of clouds/precipitation
Physical- flow of running water
Human Activity- ____________________________________________________
Additional Notes/Summary:
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Energy powers the cycles of
matter
Matter is ______________,
never created or destroyed
The Water Cycle
Water continuously moves between the ______________, the
_________________ and the______________- 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?
 ____________________:
water turns to a gas by
evaporating from the
ocean or other bodies of
water
 ____________________:
water turns to a gas by
evaporating from the
leaves of plants
 ____________________:
burning of fuels –
produces water (and
carbon dioxide)
 ____________________: cellular respiration by all organisms produces
water (and carbon dioxide)
Additional Notes/Summary:
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Once water vapor is in the atmosphere, winds can transport it over great distances.
 ____________________: When water vapor cools, the vapor condenses
into tiny droplets (liquid) that form clouds.
 ____________________: 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
 ________________: On land, some precipitation flows downhill along the
surface in what is called ‘runoff’, until it enters a river or stream that carries
it to an ocean or lake.
 _______________________: 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 (area storing large amounts of water)
Using the Word Bank, fill in the blank spots of the Water Cycle:
Additional Notes/Summary:
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Nutrient Cycles
Three important nutrient cycles for living things: carbon, nitrogen and
phosphorous.
The Carbon Cycle
Carbon is a major component of all organic compounds.
 Also found in some inorganic compounds
 Example: calcium carbonate (CaCO3) – molecule that is part of animal
skeletons
 Example: carbon dioxide (CO2) - major part of the atmosphere and
necessary for photosynthesis.
Oxygen often cycles with carbon through the biosphere, particularly due to
photosynthesis and _________________________________.
Fossil Fuels: Energy rich fuels (coal, oil, and natural gas) created from
___________________________________ compounds of ancient, dead forests,
marine organisms, or other animals have been buried and transformed by pressure
and heat.
Major reservoirs (locations of__________________________) of carbon in the
biosphere include the:





Atmosphere
Oceans
Rocks
Fossil Fuels
Forests
Additional Notes/Summary:
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Use the carbon cycle diagram to answer the following questions:
What human activities contribute to
the carbon cycle?
_____________________________
_____________________________
_____________________________
_____________________________
_____________________________
What geological processes are part
of the carbon cycle? How do they
help cycle carbon through the
biosphere?
_____________________________
_____________________________
_____________________________
_____________________________
__________________________________________________________________
__________________________________________________________________
What role do you think decomposers play in the cycling of carbon and oxygen in
the biosphere?
__________________________________________________________________
__________________________________________________________________
Fill in the blanks!
Carbohydrates
Decomposers
Photosynthesis
Respiration
 Plants take in CO2 during _____________________ and use the carbon to
build macromolecules like ________________ . These nutrients then pass
through food webs to consumers.
 Organisms release carbon in the form of CO2 gas by
_____________________
 When organisms die__________________ break down the bodies, releasing
carbon to the environment.
Additional Notes/Summary:
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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.
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
__________________________ is the most abundant form of nitrogen on Earth.
Only a handful of organisms – certain types of ________________ – can use this
form directly.
- They “_____________” (=fix) the nitrogen into usable forms
- The usable forms can then be used by other organisms
- Thus, nitrogen-fixing bacteria are an essential part of the nitrogen cycle.
Nitrogen Fixation: The conversion of Nitrogen Gas into Ammonia, Nitrates, and
Nitrites by bacteria.
 Some of these bacteria live in the soil whereas others live on the roots of
certain plants called legumes (ex. peanuts, peas, soybeans).
 ____________________ are the driving force of the nitrogen cycle!
Once these forms of nitrogen are available, primary producers can use them to
make ___________________________ and ______________________________.
Additional Notes/Summary:
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Consumers eat the producers and reuse nitrogen to make their own nitrogencontaining compounds
(and so on through the
food web).
Use the diagram of the
Nitrogen cycle to answer
the questions below:
What is the process of
denitrification?
__________________________________________________________________
__________________________________________________________________
What is the process of Atmospheric Nitrogen Fixation?
__________________________________________________________________
__________________________________________________________________
How do humans add nitrogen to the biosphere?
__________________________________________________________________
__________________________________________________________________
Eutrophication: excess growth of algae due to increased levels of fertilizers in the
water.
- Algae takes oxygen from other organisms and may release toxins
Additional Notes/Summary:
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Community Interactions
Competition- when organisms attempt to use the same limited ecological resource
in the same place at the same time.
Predator-Prey Relationships
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.
Give an example of a predator-prey relationship that you may see in your own
local ecosystem.
__________________________________________________________________
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.
Give an example of herbivory you may see in your own local ecosystem.
__________________________________________________________________
Additional Notes/Summary:
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Analyze the graph to answer the following 2 questions:
After letter A on the graph, the red line drops down. Why does the blue line drop
down shortly after?
__________________________________________________________________
__________________________________________________________________
Suppose an infection kills most of the prey at point B, how would the populations
of both predator and prey be affected at points C & D?
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
Keystone Species: a single species that is not usually abundant in a community yet
exerts strong control on the structure of a community.
Explain why an otter is a keystone species.
__________________________________________________________________
__________________________________________________________________
__________________________________________________________________
Additional Notes/Summary:
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Symbioses
Symbiosis: any relationship in which two species live closely together
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.
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): _______________________________________
2. Parasitism –
a. Who benefits?
One Species Both Neither
b. Who is harmed? One Species Both Neither
Example(s): _______________________________________
3. Commensalism –
a. Who benefits?
One Species Both Neither
b. Who is harmed? One Species Both Neither
Example(s): _______________________________________
Additional Notes/Summary: