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Body Lab 3-5 / Week 06 / Wednesday
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Week 06 · Digestion

Wednesday

The mixing bag
// Food's long trip, powered by the Sun
⏱ about 15 min

Wednesday: The Mixing Bag

Rocket turns on his kitchen mixer invention. Whirr! The bowl spins and spins.

"What if my stomach had one of these?" he jokes.

Raven tilts her head. "What do you notice about how a mixer turns lumps into a smooth mix?"

Nova hovers near the bowl. "Your stomach mixes too," she says. "But it uses muscles and juices, not a motor."

Meet your stomach

Your stomach is a stretchy sack shaped like the letter J.

It sits at the bottom end of the esophagus.

Strong muscles in its walls churn and mash the food.

The walls also make digestive juices called gastric juices.

Slowly, the food turns into a thick, liquid mix.

Three big jobs

  • Job 1: Store the food you just ate.
  • Job 2: Break the food down into a liquid mix.
  • Job 3: Slowly empty that mix into the small intestine.
Safety first
This is a model. Nothing in the bag is eaten or tasted.
A grown-up checks that the bag is sealed tight.
Squeeze gently over a tray or sink in case of drips.
Throw the bag away when you are done. Wash your hands.
  1. Put a few small pieces of bread in a zip-top bag.
  2. Add a little water. This stands for the gastric juices.
  3. Seal the bag. A grown-up checks the seal.
  4. Squeeze and mash the bag with your hands for one minute.
  5. Look at the mix. How has the bread changed?
STOMACH CHECK
  • Read the question.
  • Tap your answer.
What shape is the stomach?
In the bag model, what do your hands stand for?
In the bag model, what does the water stand for?
THE STOMACH'S THREE JOBS
  • ?Store the food you just ate.
  • ?Churn and mash it into a liquid mix.
  • ?Slowly empty the mix into the small intestine.
WHY THIS EXERCISEThe stomach stores food, mashes it, then slowly passes it on.
StatementTrue or false?
The stomach is a stretchy sack.?
The stomach dumps all the food out at once.?
Gastric juices come from the stomach walls.?
The stomach has strong muscles in its walls.?
WHY THIS EXERCISEThe stomach empties its liquid mix slowly into the small intestine.
What letter is the stomach shaped like? Type one letter.
WHY THIS EXERCISEThe stomach is a stretchy sack shaped like the letter J.
Stomach walls make ____ juices.
The stomach slowly empties into the ____ intestine.

Mighty mixing! Tomorrow food takes the longest part of its trip.

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