ENVIRONMENTAL SCIENCE MIDTERM
EXAM REVIEW
By Mrs. Shaw
DAY 1 OPENING ASSIGNMENT
 What
is the difference between the
following
 A conjecture and a hypothesis
 A scientific theory and a
scientific law
DAY 2 OPENING ASSIGNMENT
1.
2.
3.
What are the different ways that carbon gets
into the atmosphere?
In the nitrogen cycle, how is nitrogen fixed in
order to make a usable form that plants and
animals use.
What differentiates the phosphorous cycle
from the other cycles we learned about?
Unit 1 – Nature and Process of Scientific Investigations
CONJECTURES


VS.
HYPOTHESES
A conjecture is an idea about the universe, but
it's little more than speculation; comes from a
persons memory, no research has been done.
A hypothesis is a prediction of what you expect
to happen and why; it means that someone has
thoroughly researched the topic and hasn't
found any contradictions.
WHAT
ARE
VARIABLES?
A variable is any factor that can be controlled or
changed in an experiment. There are 3 types of
variables:



Dependent: the variable that is measured or
observed for a response
Independent: the variable that you change in
the experiment – remember there can only be
one!
Controlled or constant: the variable that does
not change during the experiment
PRACTICE
Roselynn did an experiment to see what type of soda
produced the highest geyser in the soda and Mentos
lab. She tested diet cola, regular cola, and cherry cola
using 7 mint Mentos in each test.

What is her dependent variable?

What is her independent variable?


List 3 things that need to be constants in order for the
test to be valid.
Why is it important to only test one variable at a time?
PRACTICE
Mrs. Shaw’s awesome science class built a catapult
out of craft sticks, glue, and a rubber band. We
wanted to determine what size rubber band was
best for launching a gumball across the classroom.
If the rubber band was too small, the gumball
wouldn’t travel very far. If it was too big, it would
be too loose to work well. We found that a rubber
band with a circumference of 11 cm shoots the
gumball the farthest.

What is the dependent variable?

What is the independent variable?

List 3 things that need to be constants in order for
the test to be valid.
SCIENTIFIC THEORIES VS SCIENTIFIC LAWS

Scientific Theories are evidence based
explanations of WHY things happen in nature.


Examples; the Theory of Continental Drift, Big Bang
Theory, etc.
Scientific Laws are evidence based descriptions of
WHAT will happen usually based on a
mathematical equation.

Examples: Newtons Laws of Motion F=ma
DATA ANALYSIS
 Mean

(a.k.a. average)
Total sum of all numbers (data) divided by the
number of observations
 Median
(a.k.a. middle)
Rank all numbers (data) from lowest to highest, the
median is the number in the middle
 If there is an even number of data then average the
two middle numbers to calculate the median

 Mode

(a.k.a. most)
The number (data) that occurs most frequently
 Range

The difference between the largest and the smallest
values
PRACTICE


Data set:
WITH
DATA ANALYSIS
6, 4, 5, 10, 5
First step: Put them in order from lowest
number to highest:

4, 5, 5, 6, 10
Mean: (average) 6
 Median: (middle) 5
 Mode: (most) 5
 Range: (difference) 6

SCIENCE



IS
DIFFERENT
Scientists need to be able to repeat
experiments in order to validate the
experiment (check for accuracy).
Science is different from other fields of study
in that it is based on EVIDENCE. Evidence can
be qualitative (observed using your senses) or
quantitative (measureable).
So if I said to you . . .”How are you going to
quantify your results?” . . what are you going
to tell me?
Unit 1B – Many Planets, One Earth
REQUIREMENTS

FOR
LIFE
ON
EARTH
The Earth
Is in the exact right location . . .far enough away and
also close enough from the Sun to receive the energy
we need for life
 Has liquid water
 Has free Oxygen in the atmosphere

TO UNDERSTAND HOW WE HAVE LIFE ON EARTH



We need to know how the
Earth first formed. . . .
Our solar system formed
from a solar nebula, a
cloud of gas and dust,
that collapsed and
condensed about 4.56
billion years ago.
Most of the matter
formed the Sun but the
rest formed the planets
and other bodies in our
solar system
HOW DO WE KNOW THAT THE CLOUD OF GAS AND
DUST TURNED INTO OUR STAR, THE SUN, AND
PLANETS?
 The
Universal Law of Gravitation – everything
with mass has gravity and is attracted to
everything else with mass.
 Where
is our evidence of this??
 http://www.youtube.com/watch?v=bFTYl07Plw
w
WHAT


IS A
NEGATIVE FEEDBACK
RELATIONSHIP?
A negative feedback system involves something being
regulated at an optimal level. If the item being
regulated goes outside the level that it functions best,
something will occur to counteract that level and bring
it back to within range.
For example . . . .your body temperature should be
somewhere between 97 – 99 degrees Farenheit. If your
body temp. rises or falls below this level, your body
will form a reaction to try to bring it back to where
your organs can function best.
EARTH’S 4 SPHERES
Matter on Earth is liquid, solid, or gas
Earth’s 4 spheres “store” matter
1. Atmosphere
2. Hydrosphere
3. Geosphere
4. Biosphere
THE NEGATIVE FEEDBACK RELATIONSHIP BETWEEN
OUR GLOBAL TEMPERATURE AND ROCK WEATHERING
As temperature increases = weathering rate
increases
As weathering increases = CO2 consumption
increases
As temperature decreases = weathering rate
decreases
As weathering decreases = CO2 consumption
decreases
BIOGEOCHEMICAL CYCLING


Biogeochemical Cycling is the cycling of
Earth’s main elements through the living and
nonliving systems on Earth (biosphere,
geosphere, hydrosphere, atmosphere).
These main elements or compounds are
Carbon, Nitrogen, Water, Oxygen, Sulfur and
Phosphorous.
CARBON “SOURCES”

“SINKS”
Sources – ways that carbon is released into the
environment


AND
Ex: respiration, decay of organic material, burning
fossil fuels, car and factory emissions
Sinks – ways that carbon is absorbed or stored
in the environment

Ex: ocean and plants
NITROGEN CYCLE
Nitrogen fixing
BACTERIA in the
soil are responsible
for changing the
atmospheric
nitrogen into a
usable form that
plants and animals
can ingest.
PHOSPHOROUS CYCLE
The phosphorous
cycle is the only one
that does not include
the atmosphere in it’s
cycling
EUTROPHICATION


Eutrophication is the increase in nutrients in a
body of water and the effect of this is primarily
an increase in algae growth.
The increase in algae growth causes a lack of
photosynthesis, decrease in oxygen levels and
then a loss of biodiversity.
WHAT
DOES THE TERM
FOOTPRINT MEAN?


ECOLOGICAL
An ecological footprint is the measure of the
demand that you place on the resources on
Earth. In other words the amount of resources
that you require to live your life. Those
resources include land, biomass, energy, etc.
You took the quiz that calculated how many
Earth’s it would take to sustain life if
EVERYONE lived like you do.
RENEWABLE

NONRENEWABLE
Renewable: a resource that is replenished or
renewed over short periods of time.


VS.
Examples: sunlight, wind energy, wave energy,
geothermal energy,
Non-renewable: a resource that is formed much
more slowly than it is used.

Examples: crude oil, natural gas, coal, copper,
aluminum and other metals.
WHAT



IS
SUSTAINABILITY?
Sustainability is the process of using these “at
risk” resources at a rate that allows them time
to renew.
Sustainability ensures that these resources will
be available for future generations.
https://www.youtube.com/watch?v=B5NiTN0c
hj0
THE WATER RESOURCES
OF
EARTH

Over 70% of our Earth's surface is covered by water ( we should really
call our planet "Ocean" instead of "Earth"). Although water is
seemingly abundant, the real issue is the amount of fresh water
available.

97.5% of all water on Earth is salt water, leaving only 2.5% as fresh
water

Nearly 70% of that fresh water is frozen in the icecaps of Antarctica
and Greenland; most of the remainder is present as soil moisture, or
lies in deep underground aquifers as groundwater not accessible to
human use.

< 1% of the world's fresh water (~0.007% of all water on earth) is
accessible for direct human uses. This is the water found in lakes,
rivers, reservoirs and those underground sources that are shallow
enough to be tapped at an affordable cost. Only this amount is
regularly renewed by rain and snowfall, and is therefore available on a
sustainable basis.
RESIDENTIAL
WATER USE



AND INDUSTRIAL
Residentially, people use the most water
gardening, landscaping, washing vehicles, and
filling up pools.
Most of our fresh water available is used for
agriculture. (47%).
In industry, water is used to transport and
dispose of wastes, as a power source
(hydropower), and as a coolant.
DESALINATION


The process by which salts are removed from water
is called desalination.
The three most common methods of desalination
are



Distillation
Reverse osmosis
Freezing
WATER PURIFICATION


The goal of
water
purification is to
remove harmful
chemicals and
microorganisms
that make water
undrinkable.
Water
purification
involves several
processes;
sedimentation,
filtration,
aeration, and
sterilization.
SEDIMENTATION


AND
FILTRATION
The first part of water purification uses
screens to remove the large items in the water.
The water is then placed in a settling tank
where the particles in the water are given time
and allowed to settle at the bottom.
Water drained from the sedimentation tank is
then sent through 1 meter of fine sand to filter
out many of the particles that were not
removed through sedimentation.
AERATION



AND
STERILIZATION
After the filtration it is time to treat the water
for taste, odor, and bacteria using aeration
and sterilization.
Aeration involves spraying water into the air
which allows bacteria that help purify it to
enter along with oxygen which is a powerful
purifying agent.
Sterilization includes using heat or chemicals
to kill any remaining bacteria or
microorganisms.
WAYS
TO DECREASE YOUR
WATER
USE
Shorter showers
 Baths instead of long showers
 Turn off water when brushing teeth
 Flush toilet less
 Water lawn less
 Wash car less

OCEAN ACIDIFICATION
BRIEF OVERVIEW


As more CO2 is emitted into the atmosphere, more is
also absorbed into the ocean. This changes the pH of
the water and makes it more acidic.
This change in pH effects organisms that have shells
by breaking down their shells or stopping them from
being able to form. It also hurts coral reefs which are
primarily made of calcium carbonate.
Unit 4 - Ecosystems
PRODUCERS, CONSUMERS,
AND
DECOMPOSERS
Producers organisms that can make their own
food (autotrophs) using light energy
(photosynthesis) or chemical energy
(chemosynthesis)..
Consumers- organisms that cannot make their
own food and get their energy from eating other
organisms. (heterotrophs)
Decomposers-such as bacteria and fungi, feed by
chemically breaking down dead organic matter.
Notes 
Symbiotic Relationships

Biologists recognize three main classes of
symbiotic relationships in nature: mutualism,
parasitism, and commensalism.

Any relationship in which two species live
closely
together
is called
symbiosis,
Mutualism:
When both
organisms
benefit which
+
means “living together.”
Parasitism: when one benefits and the other is harmed
Commensalism: When one organism benefits and the
other is not effected
 + :/
+
BIOMASS (ADD
TO
STUDY GUIDE)
Biomass is the total
amount of organic matter
available in a trophic level.
Three hundred trout are needed
to support one man for a year.
The trout, in turn, must consume
90,000 frogs, that must
consume 27 million
grasshoppers that live off of
1,000 tons of grass.
-- G. Tyler Miller, Jr., American
Chemist (1971)
Trophic Levels and Energy Pyramids
• Each step in a food chain or
food web is called a trophic
level.
• Primary producers always
make up the first trophic
level.
• Energy pyramids- show the
amount of food energy
available at each trophic
level
REMEMBER
THAT
...
Only approximately 10% of the
total biomass of the trophic
level is available for use as
energy by the higher trophic
level.
The other 90% is used to allow
for function, growth,
reproduction, and heat loss in
the original organisms.
Trophic Levels and Energy
Pyramids
Energy is lost:
as heat
through cellular respiration.
this energy is used to carry out functions of living
things such as producing new cells, regulation of
body temperature, and moving around
ONLY 10% IS AVAILABLE TO TRANSFER TO
THE NEXT TROPHIC LEVEL
PRACTICE
1. Identify the
producer, first
level consumers,
and 2nd level
consumers.
2. Give and example
of where the
decomposers
would fit into this
web.
3. Which animals are
herbivores?
PRACTICE

If there are 7000
kilocalories of energy at
the producer level, how
many kilocalories will
be available to the
tertiary consumers?
WHAT IS BIOMAGNIFICATION? (ADD TO STUDY GUIDE)


Biological magnification is the increasing concentration of a
pollutant in organisms at higher levels because the pollutants are
ingested but not secreted.
In the example the eagle eats the fish that have eaten the insects
that have been exposed. The fish will eat many insects that may
have been exposed and the eagle will eat many fish that have eaten
the insects. This will cause the amount of toxins in the larger
animals to be significantly higher in percentage than the percentage
in the smaller ones.
HUMAN
TOXINS
BODY SYSTEMS AFFECTED BY PESTICIDES AND
The Endocrine
system
functions to
produce
hormones
which are
chemical
messengers
that keep our
bodies
functioning
maximally.
The Nervous system functions
to transmit messages to the
brain and back out to tell our
bodies how to react.
HUMAN
BODY SYSTEMS AFFECTED BY
PESTICIDES AND TOXINS
The Digestive
system functions
to break down
food for
absorption as
chemical energy
for our cells to
function and also
to excrete wastes.
WHAT
AGE GROUP IS MOST AFFECTED BY
PESTICIDES OR TOXINS AND WHY?

Children ages 0-15 are MOST affected by
environmental toxins and have the highest
levels for a few reasons.
1.
they get exposed more due to the fact that they
put more things in their mouths that adults.
2.
They have less control over what they are
exposed to.
3.
Their body systems are still developing and are
more vulnerable to negative effects because of
this.
VOCABULARY BINGO

Fill in your bingo board with any combination of
these words
Conjecture
Hypothesis
Dependent variable
Independent variable
Constant
Scientific theory
Scientific law
Mean
Median
Mode
Range
Eutrophication
Ecological footprint
Sustainability
Renewable resource
Nonrenewable resource
Desalination
Freezing
Distillation
Reverse Osmosis
Water Purification
Sterilization
Aeration
Sedimentation
Filtration
Biomass
Biomagnification Symbiosis
Producer
Consumer
Parasitism
Commensalism
Mutualism