process of digestion in humans. explain.
Answers
Digestion works by moving food through the GI tract. Digestion begins in the mouth with chewing and ends in the small intestine. As food passes through the GI tract, it mixes with digestive juices, causing large molecules of food to break down into smaller molecules. The body then absorbs these smaller molecules through the walls of the small intestine into the bloodstream, which delivers them to the rest of the body. Waste products of digestion pass through the large intestine and out of the body as a solid matter called stool.
Table 1 shows the parts of the digestive process performed by each digestive organ, including movement of food, type of digestive juice used, and food particles broken down by that organ.
Table 1. The digestive processOrganMovementDigestive Juices UsedFood Particles
Broken DownMouthChewingSalivaStarchesEsophagusSwallowingNoneNoneStomachUpper muscle in stomach relaxes to let food enter and lower muscle mixes food with digestive juiceStomach acidProteinSmall intestinePeristalsisSmall intestine
digestive juiceStarches, protein, and
carbohydratesPancreasNonePancreatic juiceStarches, fats, and
proteinLiverNoneBile acidsFats
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■ MOUTH:-
♤ FLUID CALLED SALIVA SECRETED BY THE SALIVARY GLANDS.
♤ THE SALIVA CONTAINS AN ENZYME CALLED SALIVARY AMYLASE.
♤ FUNCTION :- BREAK DOWN STARCH INTO COMPLEX MOLECULE TO GIVE SUGAR.
HELP IN MOISTENS THE FOOD EASY FOR CHEWING AND SWALLOWING
■ OESOPHAGUS:-
♤ THE CANAL HAS MUSCLES THAT CONTRACT RHYTHMICALLY TO PUSH THE FOOD FORWARD & THIS MOVEMENT OF FOOD IS CALLED PERISTALTIC MOVEMENT WHICH OCCURS ALONG THE G.UT.
■ STOMACH:-
♤ GASTRIC GLANDS ARE PRESENT IN STOMACH.
♤ IT RELEASE HYDROCHLORIC ACID (HCL).
♤ FUNCTION:- KILL HARMFUL BACTERIA THAT ENTERS WITH THE FOOD.
MAKES THE MEDIUM ALKALINE.
♤ PEPSIN:- THEY ARE PROTEIN DIGESTED ENZYME.
♤ MUCUS:- PROTECTS THE INNER LINING OF THE STOMACH FROM THE ACTION OF HYDROCHLORIC ACID.
■ SMALL INTESTINE:-
♤ THE EXIT OF FOOD FROM THE STOMACH IS REGULATED BY A SPHINCTER MUSCLE.
♤ IT HELPS IN DIGESTION OF CARBOHYDRATES, PROTEINS AND FATS.
■ LIVER :- IT SECRETE BILE JUICE IN GALL BLADDER.
♤ FUNCTION:- TURN ACIDIC MEDIUM TO ALKALINE.
EMULSIFY THE ACTION OF FAT.
♤ PANCREAS:- IT SECRETE PANCREATIC JUICE IT CONTAIN ENZYME LIKE:-
♤ TRYPSIN :- HELPS IN BREAK DOWN OF PROTEINS.
♤ LIPASE :- CONVERT FAT INTO FATTY ACID AND GLYCEROL.
■ INTESTINAL JUICE:- THE WALL OF SMALL INTESTINE CONTAIN GLAND WHICH SECRETE INTESTINAL JUICE.
♤ FUNCTION :- CONVERT PROTEINS TO AMINO ACIDS.
♤ COMPLEX CARBOHYDRATES INTO GLUCOSE.
♤ FATS INRO FATTY ACIDS AND GLYCEROL.
■ VILLI:- THE INNER LINING OF THE SMALL INTESTINE HAS NUMEROUS FINGER LIKE PROJECTIONS CALLED VILLI.
♤ FUNCTION:- INCREASE THE SURFACE AREA FOR ABSORPTION.
THEY ARE RICHLY SUPPLIED WITH BLOOD VESSELS WHICH TAKE THE ABSORBED FOOD TO EACH AND EVERY CELL OF THE BODY
■ LARGE INTESTINE:-
THE EXIT OF WASTE MATERIAL FROM THE BODY IS REGULATED BY THE ANAL SPHINCTER.