What do this picture and this video have in common? .

What do this picture and this video have in common?

https://www.youtube.com/watch?v=H2zLvWeyiJY

Why do we eat?

The Digestive System performs a magical transformation…

The Digestive System performs a magical transformation…

The Digestive System performs a magical transformation…

The Digestive System performs a magical transformation…

Nutrients (Glucose, Proteins, Lipids, Nucleic Acids) Vitamins Minerals

Everything our bodies need to run (except for oxygen!)

The journey of food through our digestive system: a.k.a. the “Bite”taking Journey

Big Picture: Your gut is one long tube.

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Big Picture: Your gut is one long tube.

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Peristalsis: muscle contractions that move food through body

Big Picture: Your gut is one long tube.

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Peristalsis: muscle contractions that move food through body

Sphincters: valves that open and close to regulate digestion

4 Stages of Digestive System

1) Ingestion

2) Digestion

3) Absorption

4) Elimination

Finally, EAT YOUR DOUGHNUT HOLEMOUTH: STAGE 1: Ingestion STAGE 2: Digestion begins…

Mechanical vs. chemical

STOMACH

In 5 – 10 seconds: Your doughnut travels down the esophogus (due to peristalsis) to the…

This is a sphincter: STAGE 2: Digestion continues

M u s c le c h u rn s

Pep s in ( en z ym e t h a t b rea k s d o w n p ro t e in )

Hydrochloric Acid

STOMACH DIGESTION MECHANISMS

How do we know so much about the stomach?William BeaumontAlexis St. Martin

2 to 6 hours later…your doughnut will enter the SMALL INTESTINE Where… chemical digestion continues and absorption begins!

The SMALL INTESTINE is 20 feet long

The liver and pancreas release digestive enzymes into the top of the small intestine…. CHEMICAL DIGESTION!

Only happens in the VERY start of the small intestine

-- First 10 inches

5 ft and 2 inches remain for ABSORPTION

What enables quick and efficient absorption?

VILLIVein

carrying blood to

liver

VILLI

Capillaries

THE VILLUS

SURFACE AREA ENABLES SPEEDY ABSORPTION

Vein carrying blood to

liver

VILLI

VILLI

Capillaries

TEST YOUR UNDERSTANDING:

1) What structure feature of the small intestine makes it better suited for absorption than the stomach?

2) What theme of biology does this demonstrate?

3) How is your doughnut moving through small

intestine?

5 to 6 hours later…your doughnut will enter the LARGE INTESTINE or COLON

Absorption continues… and feces are produced in preparation for…

4 . EL IM INAT ION (12 TO 24 HOU RS L ATER )

BIOLOGY IS AMAZING!: YOUR MICROBIOME

Draw and label the path the doughnut is taking/will take through your body…

• Drawings should include: – 4 stages of digestive system and locations where they

occur– Vocabulary words– For each organ, 1 example of structure enabling

function

SEE PAGE 553 of LIVING WORLD FOR SUPPORT

FIRST: https://www.youtube.com/watch?v=_QYwscALNng