Essay about Digestive system

Submitted By Sohail_187
Words: 844
Pages: 4

Test for food groups
We carried out tests on different food groups. We found both positive and negative tests which were carried out by water. When we did the non-reducing test, we done the Benedict’s test and we got a negative result and after we had finished that, we started the test again but added hydrochloric acid into the test tube. We then put the test tube into the water bath fir 10 minutes. This made the ester bond between the sugars break down so they were monosaccharaides. Therefore, the sucrose becomes glucose. We then added hydrogen carbonate to neutralize it. We added Benedict’s solution and placed it into a water bath. Every food group which was tested was in a liquid form.

Test
What It tests for
Positive result
Negative result
Benedict’s reducing test
Reducing sugars
Orange
Clear
Benedict’s non reducing
Non-reducing sugars
Yellow
Clear
Biuret test
Protein
Purple
Clear
Iodine
Starch
Blue
Yellow
Ethanol
Lipids
Cloudy grey
Clear

Food test
We have carried out tests on different types of food which are stated below. We carried out the same test like we did before, however this time we tested the food without knowing what the contents were. The diagram below shows whether the tests were positive or negative. From the results below, it shows that the crisps contained starch, single sugars and fats. The biscuits also contained starch, single sugars and fats.

Test
What they test for
Positive
Negative
Biuret
Protein (crisps)

Yes
Iodine
Starch (Biscuit)
Yes

Benedict’s reducing
Reducing sugars (Crisps)
Yes

Benedict’s non reducing
Non reducing sugars

Yes
Ethanol
lipids
Yes

Dietary nutrients
Proteins – The digestion of proteins first start off in the stomach. The hydrochloric acid in the stomach helps break down the proteins. This allows the enzymes to separate into individual amino acids. The building blocks of proteins are the amino acids. The enzyme that is responsible for breaking protein down into individual amino acids is pepsin. The hydrochloric acid converts the inactive form to an active form. Most of the protein digestion takes place in the small intestine. The pancreas is what secretes the enzymes into the digestive tract in order to further break down the protein strands into peptide chains of many amino acids. One type of enzyme that digests proteins is protease enzymes. There are different types of these enzymes and they include pepsin which is an enzyme in the stomach and also trypsin which is an enzyme in the small intestine which helps digest proteins into amino acids. These enzymes are used to break down protein bonds (also known as peptide bonds). The process of the breaking down of the peptide bonds is called hydrolysis. The protease comes together with the hydrochloric acid in the bod to break down large protein molecules. The intestines in the body then absorb the resulting molecules. The type of enzyme in the intestines is called trypsin. After protein digestion, the amino acids get sent to the blood.

Carbohydrates – The first part of carbohydrates digestion happen in the salivary gland. An enzyme in your saliva starts to break down carbohydrates. They then carry on travelling through the oesophagus to the stomach and this is the next step of digestion. The disaccharides and trisaccharides in the carbohydrates are disrupted by the hydrochloric acids in the stomach. They then enter the small intestine where it carries…