1. Do Now: Take out notebook and pencil
Would you find lung cells anywhere other than in the lungs?
Why do we have certain cells in only specific parts of the body?

2. Glue notebook templates for human body on page
Notes will go on page

3. Essential Questions
What is the main function of the digestive system and how is it structured?
What are the main organs in this system?

4. Quick Action – INB Template
Digestive System INB Template
Cut out the body system templates and glue them together.
Complete the notes on the digestive system.
© KeslerScience.com

5. Digestive System
A group of organs working together to turn food into nutrients, which the body uses for energy, growth, and cell repair

6. Here’s how it works. Mouth The beginning of the digestive tract
Chewing breaks the food into smaller pieces (physical)
Glands secrete saliva that has enzymes that mix with food and begins to break it down (chemical)
Here’s how it works.

7. Throat (pharynx) is the next stop for food
Here’s how it works.
Throat (pharynx) is the next stop for food
Both food and air pass through here
Contains the epiglottis- acts as a switch to make the food go to the esophagus and air to the trachea

8. Food then passes through the esophagus
Here’s how it works.
Food then passes through the esophagus
Muscular tube connecting throat to stomach
Uses mucus and the movement of muscles (peristalsis) to move food towards stomach
Sphincter muscle stops food from leaving stomach back up

9. Quick Action – The Digestive System
Take a think back break!
Get with a partner and discuss chemical and mechanical/physical changes. When did you first learn about these changes? What other subject were your studying when you heard about them? Now using your previous knowledge of chemical and mechanical/physical changes answer these quick questions about the digestive system. Are these actions chemical or mechanical?
1. Chewing a saltine?
2. Saliva breaking the saltine down into molecules of glucose?
3. Your tongue breaking pieces of a hamburger apart?
4. Pepsin (an enzyme) in your stomach breaking the
hamburger into amino acids?
This activity is a quick break from taking notes.
© KeslerScience.com

10. Food then enters the stomach
Here’s how it works.
Food then enters the stomach
J-shaped muscular sac that stores food and grinds and mixes it into a liquid
About the size of your two fists
Contains hydrochloric acid and enzymes that continue to break down food

11. Food then goes into the small intestine
Here’s how it works.
Food then goes into the small intestine
A tube lined with finger like projections called villi, helps absorb nutrients into the bloodstream

12. Large intestine (colon)
Here’s how it works.
Large intestine (colon)
Thicker than small intestine
Absorbs water and nutrients missed by small intestine
Processes waste so it can be excreted through defecation easily

13. Last place food goes is the rectum-
Here’s how it works.
Last place food goes is the rectum-
Receives stool from colon and releases stool

14. Quick Action – The Digestive System
Get with a partner.
Determine and label the main organs
Help each other to remember the names and locations of the main organs in the digestive system.
Label each organ.
This activity is a quick break from taking notes.
© KeslerScience.com

15. Accessory Organs
Not part of the path of food but play a role in digestion
Teeth-cutting and grinding down food
Tongue- helps push food back to swallow
Salivary glands- moistens and lubricates food and begins to chemically break down food
Liver- produces bile
Gallbladder- stores and recycles bile
Pancreas- secretes enzymes to further digest food

16. Quick Action – The Digestive System
RECTUM
ESOPHAGUS
GALL BLADDER
TEETH
TONGUE
Add accessory organs to your digestive system diagram.
Check your answers.
This activity is a quick break from taking notes.
© KeslerScience.com

17. Digestive System Video
Digestive System Timeline