Transcript cracker lab - Plummer Pumas Science

What body system has
the function of breaking
down food for
absorption into the
blood?
• What are some ways a
cracker can be broken down
by the body in order for its
nutrition to be absorbed into
the body?
• Brainstorm ideas on sheet of notebook paper.
Cracker Lab
• 1. Each student takes 1/4 saltine cracker and
places in in the tongue in the mouth.
• 2. Students record their observations after 30
seconds.
• 3. Each student takes 1/2 cracker and chews
then records their observations after 30
seconds.
• After reading p. 484, students classify which
activity provided evidence for physical and
chemical change.
Physical: teeth grind food into smaller pieces
Chemical: Saliva breaks down food into mush
• 5. After reading p. 484, students then swallow
the cracker and records observations after 30
seconds and classified that evidence of
digestion in the esophagus
• 6. Confirm peristalsis- the contraction and
relaxation of muscles of the esophagus
moving food down to the stomach- with
demonstration of a ball squeezed down a
tube sock.
• Record what you observed.
• After reading p. 485-487, students classify
the type of changes in the stomach, small
intestine and large intestine.
Digestive system
process where
food is broken
down through
chewing, mixing
and churning.
Muscles in
the
stomach
grind food
into smaller
pieces
Gastric juice
and
hydrochloric
acid made in
stomach break
apart large
protein
molecules
Peristalsis
slows down
Muscles in the
rectum release
the semisolid
waste from the
body
Excess water is
absorbed from
the chyme
Peristalsis
continues
to move
and mix
the chyme
Where most
chemical
digestion occurs:
bile breaks down
fat particles.
Carbohydrates,
proteins, and fats
are broken down
from bile.
• Students create a Venn diagram to
compare and contrast the evidence of
physical and chemical changes in the
digestive system