DIGESTIVE SYSTEMDIGESTIVE SYSTEM

WHAT IS THE JOB OF THE WHAT IS THE JOB OF THE DIGESTIVE SYSTEM?DIGESTIVE SYSTEM?

TO BREAK DOWN FOOD INTO BIOMOLECULES THAT CELLS CAN USE.

WHERE DOES DIGESTION WHERE DOES DIGESTION BEGIN?BEGIN?

THE MOUTH- begins mechanical digestion

HOW IS FOOD MECHANICALLY HOW IS FOOD MECHANICALLY BROKEN DOWN IN THE MOUTH?BROKEN DOWN IN THE MOUTH?

CHEWING WITH YOUR TEETH BREAKS FOOD INTO SMALLER PIECES.

HOW IS FOOD CHEMICALLY HOW IS FOOD CHEMICALLY BROKEN DOWN IN YOUR MOUTH?BROKEN DOWN IN YOUR MOUTH?

BY SALIVA THAT CONTAINS ENZYMESEnzyme called amylase begins to

break down starches

Food moves from the mouth to Food moves from the mouth to the esophagus….the esophagus….

the tube connecting your mouth to your stomach.

THE ESOPHAGUS MOVES THE THE ESOPHAGUS MOVES THE PARTIALLY DIGESTED FOOD TO THE…PARTIALLY DIGESTED FOOD TO THE…

STOMACH- continues mechanical digestion by churning food.

WHAT IS PERISTALSIS?WHAT IS PERISTALSIS?

SMOOTH MUSCLES THAT CONTRACT TO MOVE FOOD DOWN THE ESOPHOGUS

GASTRIC JUICE IS RELEASED INTO THE GASTRIC JUICE IS RELEASED INTO THE STOMACH TO BREAKDOWN FOOD. WHAT IS STOMACH TO BREAKDOWN FOOD. WHAT IS

GASTRIC JUICE?GASTRIC JUICE?

A MIXTURE OF MUCUS, WATER, ENZYMES, & ACIDS

Hydrochloric acid (stomach acid) has a pH of about 1-2. Very acidic!

WHERE DOES THE FOOD GO ONCE WHERE DOES THE FOOD GO ONCE IT LEAVES THE STOMACH?IT LEAVES THE STOMACH?

TO THE SMALL INTESTINE

Intestines have many foldsIntestines have many folds

Folds are called villiThey increase surface area to absorb

nutrients

PANCREATIC ENZYMES WILL PANCREATIC ENZYMES WILL HELP FINISH BREAKING DOWNHELP FINISH BREAKING DOWN

CARBOHYDRATES AND PROTEINS

THE LIVER MAKESTHE LIVER MAKES

BILE- BREAKS DOWN FATS

YOUR DIGESTED FOOD MOVES INTO YOUR BLOOD YOUR DIGESTED FOOD MOVES INTO YOUR BLOOD STREAM. WHERE DOES THE UNDIGESTED FOOD AND STREAM. WHERE DOES THE UNDIGESTED FOOD AND

EXCESS WATER GO?EXCESS WATER GO?

TO THE LARGE INTESTINE

WHAT HAPPENS TO THE WHAT HAPPENS TO THE EXCESS WATER?EXCESS WATER?

IT IS REABSORBED INTO THE BODY THROUGH THE WALLS OF THE LARGE INTESTINE

DIARRHEA OCCURS WHEN…DIARRHEA OCCURS WHEN…

Your large intestine can’t reabsorb excess H2O…

This makes your stool (feces) watery!

WHAT HAPPENS TO THE WHAT HAPPENS TO THE UNDIGESTED FOODUNDIGESTED FOOD

IT IS EXPELLED FROM THE BODY

FOOD NEVER PASSES THROUGH THE FOOD NEVER PASSES THROUGH THE LIVER OR PANCREAS FOR DIGESTION.LIVER OR PANCREAS FOR DIGESTION.

MOUTH ESOPHAGUS STOMACH SMALL INTESTINE LARGE INTESTINE WASTE LEAVES THE BODY.