The Digestive Process Begins

What are the three functions of the digestive system?

Functions of the Digestive System

1. Breaks down food into molecules the body can use

2. The molecules are absorbed in to the blood as nutrients and carried throughout the body

3. Wastes are eliminated from the body

Organs of the Digestive System

2 Types of Digestion Digestion- process by which body

breaks down food into small nutrient molecules

2 Types of Digestion

Mechanical Digestion Chemical Digestion

Mouth Stomach

Small Intestines

StomachMouth

What happens in the mouth?

What happens in the mouth? Digestion starts in the mouth BOTH: mechanical and chemical

digestion occur in the mouth Mechanical digestion- chewing food

using your teeth, saliva softens the food to make it easier to chew and swallow

Chemical digestion- saliva breaks down starch into sugars

Saliva is an enzyme called amylase

What happens in the mouth?

Esophagus

Esophagus

What happens in the esophagus?

What happens in the esophagus? Esophagus- Muscular tube that connects

mouth to stomach After you swallow the food it travels to the

stomach (in about 10 seconds) Turn to p.521 and answer the following on your

note guide: Describe peristalsis. Why do you think the esophagus is lined with

mucus? How does the epiglottis prevents food from

entering your lungs?

PeristalsisOccurs in esophagus, stomach, small & large intestines

What happens in the esophagus?

What happens to food in the stomach?

Turn to p.p. 522-523 and answer the questions on your note guide.

Do mechanical and/or chemical digestion occur in the stomach?

What are digestive juices? Since digestive juices are so strong, why

doesn’t it burn a hole in your stomach?

Inside the Stomachpage 523

The Stomach

The Stomach

What happens to food in the stomach?

Stomach Ulcer

Review