Science Report

Title :ABSORPTION OF DIGESTED FOOD Aim:To show the absorption of the glucose through a visking tube. Probelem:How does the absorption of the glucose take palce in the visking tube? Hypothesis:Glucose can diffuse through a visking tube. Manipulated variables:Types of food(starch and glucose). Responding variable:Diffusion of food. Fixed variables:Visking tube, time,temperature Materials:1% starch solution,10% glucose solution,Benedict’s solution,iodine solution,visking tube,distilled water cotton thread. Apparatus:Beaker,tripod stand,wire gauze,bunsen burner,stopwatch,boiling tubes,test tubes. Procedure: 1) Two boiling tubes A and B was labelled. 2) Two visking tube were soaked into the water to sofften them. 3) The and of the visking tube was tied with cotton thread. 4) The visking tube was filled with 10cm3 of strach solution. 5) The other end of the visking tube was tied with coton thread. 6) The external surface of the visking tube was thoroughly with distilled water. 7) Steps 3 to 6 were repeated with another visking tube was throughly with distilled water.

8)

The visking tube were placed into boiling tubes A and B which had been filled with water earlier.Subquently stopwatchles were started for countdown.

2cm3 of water surrounding the visking tube was immediately poured into 2 test tubes.One test tube were tasted with iodine solution while the other onewas tasted with Benedict’s solution. 10)After 30 minutes,steps 9 were repeated 9)

Boiling water

Food test

At the beginning of the experiment observation inference

A B

Iodine test Absent Benedict’s Absent test Iodine test Absent Benedict’s Absent test

Starch absent Glucose absent Starch absent

The end of the experiment observation inference

Blueblack No reaction No reaction

Glucose Red absent colour

Starch absent Glucose absent Starch absent Glucose absent

Questions: 1) What is the importance of step 6? 2) If the visking tube represents a portion of your small intertine,what would the distilled water surrounding the visking tube represent? 3) Which food diffuses through the visking tube?why? 4) Based on your result,explain the obsorption of carbohydrates in the gut.

Answers: 1) To ensure the starcd and the glucose clean from the outside of the visking tube. 2) Blood. 3) Glucose,because the glucose molecules is small. 4) Starch molecules are big and cannot go through the wall of visking tube. Conclusion:The hypothesis can be accepted.so,the conclusion is glucose diffuses through the wall of the small intestine into the bloodstream

Classifying: FlOUR,MARGARINE,CARROT

Milk,Fish

carbohydrat es

Protein

Fats

Vitamin

Flour

Fish

Margarine

Milk

Mineral

Carrot

Appucation Of idea :Big molecules like those of protien and fat cannot diffuse through the of the small intestine. Reflection:Protein is broken down to amino acids,fat is broken down to fatly acids and glycerol before they can be absorbed through the walls of the small intestine.