Testing for LifeMaterials per group q data sheet q nonfiction book: Living and Non-Living Things q 2 non-living objects e.g., rock, pencil, paper clip, pasta q 1 piece of fruit q water q
Trang 1Testing for Life
Materials
(per group)
q data sheet
q nonfiction book:
Living and Non-Living Things
q 2 non-living objects (e.g., rock, pencil, paper clip, pasta)
q 1 piece of fruit
q water
q disposable cup (per class)
q 1 live, sprouting plant
q 1 live insect in clear container
Purpose
To compare living and non-living things and develop
tests to tell the difference
Process Skills
Observe, Collect data, Interpret data, Identify and control
variables, Draw conclusions, Design experiments
Background
The world is made up of both living and non-living
things There are important differences between the two
In order for something to be classified as living, it must:
exploration, students will use what they have learned
in this unit to design tests and then to apply those tests
to a variety of things in order to determine which things
are living and which are not
(some testing may be done over several days)
Procedure
learned about the differences between
living and non-living things Encourage
and Non-Living Things for review Explain
to students that today they will examine
a group of things and try to decide which
ones are living and which ones are
non-living To do this, they will come up with
several tests to apply to the things they
will examine
living things they feel can be tested in
class and which cannot Have students
explain their reasoning Present the
data sheet to students and explain the
exploration Groups will evaluate items
on as many of the criteria as they can,
circling yes or no in the appropriate
column Those criteria that cannot be tested in class should be left blank for now After testing, the groups will discuss their answers for the remaining criteria
Trang 23 Give each group of students the same
set of six items, including two non-living
items, a cup of water, and a piece of
fruit Also display a live insect in a clear
container and a live, sprouting plant
Help students identify all the items
one of the six criteria for living things
described in the book Distribute a copy
of the data sheet to each group Explain
to students that the left-hand column is
where they will list all the items they are
testing The middle columns are where
students will record the results of their
test(s) The right-hand column is where
students will conclude whether each item
is a living or non-living thing, based on
the results from the middle columns
5 Instruct students to list all the items in
the first column of their data sheets (or
prepare the sheet before making copies)
Then have students discuss as a group
which criteria they feel they can test for
in class, and how they can test for the
criteria they have chosen Some criteria
may best be judged by discussion rather
than by testing.
Below are suggestions for three of the six criteria that may be possible to test:
• Living things grow and develop: Students
might give each item light, water, and nutrients, and then observe over several days whether it grows or develops in any way If a change cannot be observed, students may base their judgment on prior knowledge instead, such as
“Animals grow by eating and drinking.”
• Living things use energy: Students might
try feeding each item or observing whether it responds to sunlight
Alternatively, they could try depriving all items of food, water, and light and watch for any changes If a change cannot be observed, students may base their judgment on prior knowledge instead, such as “Plants need light
to survive.” [Note: Care should be taken
to protect the live insect from harm.]
• Living things respond to their environment:
Students might change the temperature
or lighting around the items, make sounds, or wet the item to see whether any responses occur If a response cannot be observed, students may base their judgment on prior knowledge instead, such as “Plants sometimes wilt in the heat.”
Below are suggestions to guide a discussion
of three criteria that may not be easy to test:
• Living things are made of cells: Students
might discuss whether, if they could look at the item up close with a microscope, they would see tiny cells that are (or used to be) alive
Students may need teacher input to fill in this column
Collect Data
Item tested
develops Needs energy Reproduces Is of Responds Adapts
Is the item living or non-living?
apple YES
NO YES NO YES NO YES NO YES NO YES NO LIVING NON-LIVING
plant YES
NO YES NO YES NO YES NO YES NO YES NO LIVING NON-LIVING
water YES
NO YES NO YES NO YES NO YES NO YES NO LIVING NON-LIVING
rock YES
NO YES NO YES NO YES NO YES NO YES NO LIVING NON-LIVING
Name Date _
Directions: In the first column, list the items you will test As you test and discuss each item, circle
YES or NO for each test Once all six tests have been completed, circle LIVING or NON-LIVING
in the last column.
Trang 3• Living things reproduce: Students might
discuss whether it would be possible
for new forms of the item to develop
from the original item
• Living things adapt: Students might
discuss whether they think the item
(or other similar items) would change
over time if it were moved into a very
cold or warm place, or into a place
with hungry animals
for the criteria they have chosen For
each item, students should circle yes or
no for the test at the top of the column
Everyone in the group should be invited
to discuss the results Encourage students
to leave a box blank if they are unsure
about an answer Discuss these later as
a class
items for all six criteria, have them share
their results The rest of the groups should
listen and fill in their data sheets for any
columns they were unable to complete
They should complete the final column
by circling living or non-living Only
those items for which yes was circled
in all six columns should be identified
as living things If the teacher or students
disagree with the final analysis of living
or non-living, go back through the test
results in that row and determine
whether any results may need to be
revised for accuracy Remind students
that even items that are no longer alive
are classified as living things They were
once alive, or they were part of something
that was alive
Discussion Questions
Use these questions to guide a discussion about the experiment
non-living?
The insect, live plant, and piece of fruit are living things The cup of water and the other two items are non-living.
seem easiest to test? Why?
Students may conclude that judging whether something responds to its environment or whether it grows and develops would be easiest to test, because the results can
be seen soonest.
seem most difficult to test? Why?
Students may conclude that judging whether something adapts or is made of cells would
be most difficult to test, because adaptations take a long time, and cells are too small to
be seen with just our eyes.
something is made up of cells?
A scientist would probably look at an item
up close with a microscope to determine whether it is made up of cells.
something adapts over time?
A scientist might find fossils of that living thing and compare it to current forms of the same thing to see whether any changes have occurred They may research how related organisms differ from one another because
of their differing environments Or they may follow a population of living things over time to see how it adapts to changes
in its environment.
Trang 46 Are there any other ways you would have
tested these items to decide which ones
are living and which ones are non-living?
Responses will vary, and may reveal
misconceptions See the Unit Guide for more
information on addressing misconceptions.
Conclusion
How can you tell if something is living
or non-living?
Students should reflect on the activity and conclude
that, in order to determine something is a living
thing, it must pass all six tests used in this activity
Extensions and Variations
• Inquiry Science: Give students a new,
blank data sheet Let students choose
their own items to be tested Supervise
their choices and their testing for safety
and ethical concerns
• Variation: Have each group—or the entire
class—focus on just one of the criteria and
test many objects for that one criterion
Some criteria may be best to test over
several days, such as depriving items
of sunlight or water
• Extension: Let students plant a fun garden
in which they test whether certain items will grow when given soil, water, and sunlight Items should include a variety
of seeds as well as other items students would like to test, such as marbles, erasers,
or bubble gum Label each spot in the garden with what was planted there and then have students observe it over time
• Technology: Find a variety of preselected
images online, and display one at a time for the class, using an interactive whiteboard or a projector Have students discuss whether each image shows a living or a non-living thing Try to choose some that are likely to spark debate
should have yes or no circled in all six columns Only those items with yes circled
in all six columns should also have living circled in the last column Otherwise,
non-living should be circled
Trang 5Collect Data
Item tested
develops Needs energy
Reproduces Is
Responds Adapts
Is the item living or non-living?
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
YES NO
YES NO
YES NO
YES NO
YES NO
YES NO
LIVING NON-LIVING
Name Date _
Directions: In the first column, list the items you will test As you test and discuss each item, circle
YES or NO for each test Once all six tests have been completed, circle LIVING or NON-LIVING
in the last column