Living Things and the Environment

Teacher Notes / 2
Living Things and the Environment
What’s in the Scene? / 11
Organisms and Their Habitats / 12
World in a Bottle / Pre Lab
Directed Inquiry
Open Inquiry / 13
14
18
Organizing an Ecosystem / 22
Populations
Populations / 23
Growing and Shrinking / 24
Elbow Room / 25
Interactions Among Living Things
Can You Hide a Butterfly? / 26
Adaptations for Survival / 27
Competition and Predation / 28
Type of Symbiosis / 29
Changes in Communities
How Communities Change / 30
Primary or Secondary / 31

Living Things and
the Environment

Answering the Big Question

The activities in this lesson will help students
answer the Big Question by allowing them to
explore habitats of organisms, how a habitat
meets the survival requirements of an organ-
ism, and the interactions between the living
and nonliving components of an ecosystem.

What’s in the Scene?

Inquiry Focus

Infer—using observations about living and
nonliving things in an ecosystem to infer that
organisms live in certain habitats because of
their requirements for survival

Group Size Individuals or pairs

Class Time 15 minutes

Advance Preparation (5 minutes)

1. If you need help gathering resources, ask stu-
dents to donate magazines to the classroom.

2. Set up materials in a central location for stu-
dents to pick up.

Procedure Tips

1. Encourage students to look for pictures with
views that allow them to distinguish various
living and nonliving things.

2. Depending on the photograph viewed, stu-
dents may identify water, soil, sunlight, and
air among the nonliving things.

Answers

1. Look for answers that indicate that living
things need nonliving things in order to sur-
vive, such as plants needing soil.

2. Sample Answer: The grass needs to grow
in soil. I could test this by planting grass in
something other than soil, and then observ-
ing to see if the grass survives.

Organisms and Their Habitats

Unlocking the Key Concept

This activity will help students infer the habitat
needs of an animal based on the animal’s fea-
tures, and then learn about the actual habitat.

Inquiry Focus

Infer—using current knowledge and
observations of an animal’s features to suggest
characteristics of an animal’s habitat

Group Size Individuals

Class Time 15 minutes

Procedure Tips

1. If students are having trouble with Step 1,
ask them if they have ever owned a pet, and
to consider what kinds of things pets need to
survive. Then think about how animals meet
these needs in their environments.

2. Once students have completed the activity,
reveal to students that the fossas live in the
forests of Madagascar, where they live among
trees and hunt small animals such as birds,
mice, wild pigs, and lemurs.

Answers

1. a) Sample Answer: The animal most likely
hunts other animals. It has sharp claws and
teeth, and has a stalking stance. b) Sample
Answer: The animal probably lives in trees. It
has sharp claws and a long tail that could be
used for balance.

2. Look for answers that include details about
the fossa’s habitat, including some of the
biotic factors (other plants and animals) and
abiotic factors (water, minerals, soil, light,
and climate) that can be found there.

World in a Bottle

Unlocking the Key Concept

Both Versions This activity will help students
learn about abiotic and biotic factors through
the construction of a terrarium.

POPULATIONS AND COMMUNITIES

Answers—Pre Lab

Both Versions:

1. Qualitative observations may be the color,
weight (heavy, light), and texture. Quantita-
tive observations may be length, width, or
height measurements; weight measurements;
or number of pages.

2. The scientific observations include the quali-
tative and quantitative data: the number of
fins, the color, and the length. “The fish is
sick” and “The fish is happy” are not scien-
tific observations. Stating that a fish is sick
simply by looking at it is an assumption or
judgment based on other observations. For
example, the fish may be moving slowly, not
eating, or swimming on its side. We might
conclude from these observations that the
fish is sick, but this is not a fact. Stating that
a fish is happy is assigning a human emotion
to a fish, an example of anthropomorphism.

Do the Math

Look for answers that include numerical data,
such as the number of legs, the length of the
legs (in centimeters), and the diameter of the
body (in centimeters).

Inquiry Focus

Directed Inquiry:

Make Models—creating a physical representa-
tion of an ecosystem to explore the interactions
between biotic and abiotic factors

Observe—gathering and recording data about
how organisms interact with each other and
with their environment

Predict—making an educated guess about the
outcome of the experiment—whether or not
the plants will survive in the terrarium

Open Inquiry:

Develop a Hypothesis—forming a testable ques-
tion about the functioning of a terrarium

Observe—gathering and recording data about
how organisms interact with each other and
their environment

Control Variables—developing an experiment
in which one variable is manipulated and the
others are controlled

Group Size

Both Versions Pairs or groups

Preparation Time

Both Versions 30 minutes

Class Time

Both Versions 30 minutes, plus 5–10 minutes
per day over two weeks

Safety

Both Versions:

1. Be sure students wear lab aprons to protect
their clothing from soil stains.

2. Students who are allergic to molds should
not handle the soil.

3. Remind students to wash their hands after
they finish the activity.

Advance Preparation

Both Versions:

1. Prior to the lab, set materials out at each sta-
tion for students.

2. A week to two before the lab, have students
bring in 2-liter clear plastic bottles to use for
the terrariums. Cut these with scissors or a
razor blade just below the neck.

3. You can find charcoal and gravel, and pos-
sibly moss and vascular plants, at an aquar-
ium-supply store or large pet store.

4. Vascular plants such as ferns, begonias, or
violets will work well in terrariums.

Procedure Tips

Directed Inquiry:

1. Review safety guidelines for this lab.

2. Plants may outgrow the container and
become root bound. Plants may start to
decline if they become too crowded, or if
nutrients in the soil decline.
Sample Prediction: The plants will grow and
thrive as long as they receive sunlight and
enough—but not too much—water.

Open Inquiry:

1. Review safety guidelines for this lab.

2. As an introduction to the lab, set up a sample
terrarium to show students. Point out the dif-
ferent components of the terrarium that are
described in the student instructions for setting
up a terrarium. Ask students to think about
the requirements of the plants inside the ter-
rarium. For example, plants need sunlight,
water, carbon dioxide, and nutrients. Remind
students that if a terrarium is set up properly, it
can remain in balance for long periods of time.
Then have them think about what signs they
can look for to decide whether the terrarium is
in balance. For example, if the terrarium is not

POPULATIONS AND COMMUNITIES

in balance, the plants may be wilted or dead,
there may be mold, or the terrarium may have
excess water in the bottom. This will help them
as they design their experiments and need to
determine the types of data they want to col-
lect. Finally, tell students that in this activity
they will be designing an experiment to help
understand how abiotic and biotic factors
interact within an ecosystem.

3. The experimental setup should have two
terrariums. One will serve as the control
and the other will be identical, but will have
one variable changed. For example, one ter-
rarium may have twice as much water or half
as much gravel as the other. In this setup, the
manipulated variable will be the factor the
student is testing (amount of water, light,
gravel, etc.). The responding variable will
be the effect of this factor on the terrarium.
Students will probably use qualitative obser-
vations as they collect data, although some may
decide to measure the growth of the plants.

4. Have students collect data for at least two
weeks. Data tables should include a column
for the date of observation and columns to
record observations of each terrarium.

Sample Hypothesis: The amount of light affects
the success of a terrarium.

Answers—Analyze and Conclude

Directed Inquiry:

1. Biotic factors: plants and any microscopic
organisms in the soil; abiotic factors: gravel,
minerals and nutrients in soil, charcoal,
water, air, light

2. yes, light, an abiotic factor

3. Look for answers that include a statement
about whether or not the insect would
survive, as well as a logical explanation to
support the statement.

4. Sample Table:

5. Sample Answer: Set up two terrariums. The
first terrarium should have 2.5 cm of gravel
on the bottom, covered with a spoonful
of charcoal. Two vascular plants should be
placed in the terrarium and the soil packed
around the stems. Then the soil should be
sprayed with water and covered with moss
plants. The second terrarium should be
identical to the first except that the gravel
should be omitted. After the terrariums are
set up, take observations for two weeks to see
if there are any differences that can be attrib-
uted to the presence or absence of gravel.

Open Inquiry:

1. Sample Answer: Helpful data included the
plant growth and health, and the presence
or absence of mold and excess water.

2. The manipulated variable is the factor the stu-
dents changed in their second terrarium. For
example, they may have changed the amount
of water, amount of light, or number of
plants. The responding variable is the effect of
the manipulated variable on the success of the
terrarium. The control is the first terrarium,
set up following the instructions in the lab.

3. Students should be drawing conclusions
directly from their data. If their data are
inconclusive, they should state this.

4. Answers should indicate whether or not stu-
dents’ conclusions matched their predictions.

Answers—Post Lab

Directed Inquiry:

1. Answers should explain the results and
whether they match the prediction.

2. Students should explain a new setup or any
adjustments that take into account any prob-
lems encountered during the activity.

3. Sample Answer: Biotic factors depend on
abiotic factors. For example, plants depend
on light and water. If either of these are not
present in the right amount, the plants will
deteriorate. Students may have additional
questions about why certain factors affect
the balance of a terrarium.

Communicate—Sample answer: The “closed”
system still allowed light in. The small scale of
the setup limited the potential size the plant
could reach. Because the terrarium was low in
diversity, a small event like the death of one
plant could have affected the entire flow of
elements and energy in the system.

POPULATIONS AND COMMUNITIES

Open Inquiry:

1. Sources of error could include human error
in setting up two identical ecosystems. For
example, the amount of gravel may not be
exactly the same. Another source is human
error in making observations. These errors
can be minimized by making careful
measurements.

2. Most likely the students took qualitative
data. Advantages are that the data can be
more descriptive and rich with detail. How-
ever, qualitative data can be hard to analyze
in order to find trends or patterns because
it cannot be graphed. Qualitative data are
subjective, so different people may make dif-
ferent observations of the same object. Some
students may have taken quantitative data.
The advantages are that it is easier to analyze
(because it is numerical) and there is less
chance for investigator bias. The drawback
is that it may not provide the same level of
detail as qualitative data.

Communicate—Students may write about
humans upsetting the balance through actions
like greenhouse gas emissions, overfishing,
threatening endangered species, polluting, lit-
tering, overconsumption of water, and defor-
estation. Students may suggest actions like
protecting endangered species, reducing water
use, planting trees, cleaning up streams and
roadsides, conserving energy, and recycling.

Organizing an Ecosystem

Unlocking the Key Concept

This activity will help students create a dia-
grammatic representation of the four levels
scientists use to organize ecosystems: organism,
population, community, and ecosystem.

Inquiry Focus

Communicate—using diagrams to represent
the organizational levels of an ecosystem, from
smallest to largest

Group Size Pairs or groups

Class Time 20 minutes

Materials

Any small objects can be used, and the objects
of each type do not have to be identical. This
helps to reinforce the concept that traits of
organisms in a population vary.

Advance Preparation (5 minutes)

Organize materials at lab stations for each
group. Each group should have four to six of
each type of object.

Procedure Tips

Have students read the material on ecosystem
organization in their student editions. If stu-
dents are having trouble with Step 1, guide
them to start with the organism, and write in
“me,” or their names. Then have students think
about what makes up a population of people
and a community in the ecological sense.

Answers

1. Look for answers that state the item(s) chosen
for each level of organization along with a logi-
cal explanation about why they were chosen.

2. Students’ diagrams should include them-
selves as the organism, other people in the
population, other species in the community,
and nonliving things in the ecosystem.

Populations

Answering the Big Question

The activities in this lesson will help students
answer the Big Question by allowing them to
explore how scientists can estimate the number
of organisms in a population as well as the vari-
ous factors that affect the size of a particular
population.

Populations

Inquiry Focus

Form Operational Definitions—creating a
definition of the term estimate based on the
method students use to estimate the number of
beans in a jar