The Digestive SystemThe Digestive System

What is the job of the What is the job of the Digestive System?Digestive System?

To help get nutrients into the blood stream to travel to all cells.

The digestive system is one big tube. What goes in one end, goes out the other.

The digestive process takes about 24 hours to complete. (So when you’re eating supper, you’re still digesting breakfast).

How do we process How do we process food?food?

1) Digestion: Break the food down:

Mechanical Chemical

2) Absorption: Get nutrients into circulation.

3) Metabolism: Cells use the nutrients.

Steps in Steps in DigestionDigestion

MouthMouth Function:

Mechanical- chewing Chemical- food mixes

with saliva

Structure Teeth, tongue, salivary

glands.

EsophagusEsophagus Function

Pushes food into stomach.

Peristalsis- muscle contraction

(Like squeezing last bit of toothpaste out of the tube.)

Structure 25 cm long. A muscular tube

StomachStomach

Structure: muscle with thick layer

of mucous.

Function: chemical – gastric juices mechanical- muscle

contraction Break down food and

kill microorganisms.

Small IntestineSmall Intestine Function:

break down starches, fats, and proteins.

Structure: 3-6 meters long!! Coiled up

LiverLiver Function:

produce urea filter harmful substances

from blood.

Structure: about 3 lb

Gall BladderGall Bladder

Function: stores bile

Structure: located under the liver

PancreasPancreas Function:

Completes the job of breaking down protein, carbohydrates, and fats.

Structure: six inches long

VilliVilli Function:

slows down food so that nutrients can be absorbed into the blood stream

Structure: little tiny hair-like

projections that stick on intestine.

Large IntestineLarge Intestine Function:

water taken out and put back into body

All “leftovers” sent to leave body through excretion.

Structure: 1.5 meters long

What is heart burn?What is heart burn? Acid eats away at esophagus

when there is no mucous in esophagus.

What is an ulcer?What is an ulcer?

Gastric juices in your stomach that eat through the mucous lining.

Causes: Stress Bacterial infections

Digestion in ActionDigestion in Action(run time: 24 minutes)(run time: 24 minutes)