Chapter 3 Lesson 3 The Digestive Process Begins

Ms. Schreurs 7th Grade Life Science Human Body Systems

What Are the Functions of the Digestive System?

#1 Digestion – __________= the process

by which your body breaks down food into small nutrient molecules • 2 types

1. Mechanical Digestion= bites of food are torn or ground into _______________________

2. Chemical Digestion= chemicals break foods

** Figure 1 page 81**

#2 Absorption – Absorption= the process by which nutrient

molecules pass through the wall of your digestive system into your blood • Mostly in _________________________

#3 Elimination – large intestine eliminates materials not absorbed

What is the Role of the Mouth, the Esophagus, and Stomach?

• The Mouth – Where digestion begins

– Mechanical and chemical digestion begins inside the mouth

– Saliva= _____________ ______________________________________

– What does your tongue do?

• Enzymes= ______________________ ______________________________________________________________ – Different enzymes are needed to complete

the process of digestion

– Break down starches, proteins, and fats

• The Esophagus – Epiglottis= ____________________________

____________________________________

– Esophagus= a muscular tube that connects the mouth to the stomach

– Mucus= a thick, slippery substance produced by the body • Makes food move easily

– ______________= contractions that push food

• The Stomach – Stomach= J-shaped muscular pouch in the

_______________ • Mostly mechanical digestion and some chemical

digestion

The Stomach • Mechanical Digestion

– Smooth muscle in the stomach wall contract to produce a churning motion

• Chemical Digestion – Digestive juice digests

___________ (pepsin)

– High in hydrochloric acid which kills many bacteria you swallow

Chapter 3 Lesson 4 Final Digestion and

Absorption

Ms. Schreurs 7th Grade Life Science Human Body Systems

How Do the Small Intestine, Liver, and Pancreas Function?

• The Small Intestine – The part of the digestive system where most

_____________ digestion takes place

– 6 meters long, _______cm wide

– Liver and pancreas send substances to small intestine to complete chemical digestion

** Complete the graphic organizer on page 87**

• The Liver and Gallbladder – Liver= _____________________________

– Bile= substance that breaks up fat particles

– ________________= stores bile

– Bile is released when food enters the small intestine, and breaks up large fat particles into smaller fat droplets

**Complete Figure 1 on Page 88**

• The Pancreas – a triangular organ between the stomach and

first part of the small intestine

– Produces digestive enzymes to break down carbohydrates, ___________, and ________

pancreas

Absorption in the Small Intestine

• _______= increase the surface of the small intestine and assist with nutrient absorption – Nutrients pass from cells on villi into blood

vessels to be delivered to __________

What Does the Large Intestine Do?

• Large Intestine= __________________ _______________________________ – Material moves through the large intestine,

and water is absorbed into the bloodstream

– __________= end of large intestine

– Anus= eliminates waste material

** Complete this figure on page 91, refer to page 90 for directions**