Chapter 16: Regulation and Reproduction

Model a Chemical Message
Your body has systems that work together
to coordinate your body’s activities. One of
these systems sends chemical messages
through your blood to certain tissues, which,
in turn, respond. Do the lab below to see how
a chemical signal can be sent.
1. Cut a 10-cm-tall
Y shape from filter
paper and place
it on a plastic,
ceramic, or glass
plate.
2. Sprinkle baking soda on one arm of the Y
and salt on the other arm.
3. Using a dropper, place five or six drops of
vinegar halfway up the leg of the Y.
4. Think Critically Describe in your Science
Journal how the chemical moves along
the paper and the reaction(s) it causes.
Start-Up Activities
Preview this chapter’s content
and activities at
green.msscience.com
STEP 1
STEP 2
STEP 3
Stages of Life Make the following
Foldable to help you
predict the stages of life.
Fold a vertical sheet of paper in half
from top to bottom. Then fold it in
half again top to bottom two more
times. Unfold all the folds.
Refold the paper
into a fan, using
the folds as a
guide. Unfold all
the folds again.
Label as shown.
Fertilization/Embryo
Death
Read and Write Before you read the chapter,
list as many stages of life as you can on your
Foldable. Add to your list as you read the
chapter.
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(bkgd)Lawerence Manning/CORBIS, (c)John Evans