Digestion Lab Report

[Pages:9]Digestion Lab Report

David Narain Human Anatomy and Physiology II

BIO2312 OL57 12/4/2020

Introduction The human body has multiple systems that must work together in order to

maintain homeostasis thus, to sustain life. All these systems ultimately rely on the vitamins, nutrients, and energy that is absorbed from various things that are consumed by the human body. The digestion system in particular is responsible for the breakdown of food and the absorption of that food by the body and also the disposal of waste from the body. The digestion system is made up of the gastrointestinal tract and a plethora of accessory organs. The gastrointestinal tract begins at the mouth and ends at the anus, which includes the mouth, stomach, esophagus, stomach, small intestines and large intestines (Martini, 2018). Where as the accessory organs of the digestive system are the tongue, salivary glands, pancreas, liver and gallbladder (Martin, 2018). There are six integral processes that the digestion system performs; ingestion, mechanical digestion and propulsion, chemical digestion, secretion, absorption, and defecation (Martini, 2018). Digestion is important for breaking down food into nutrients, which the body uses for energy, growth, and cell repair. Food and drink must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body. The body breaks down nutrients from food and drink into carbohydrates, protein, fats, and vitamins.

In order to do this, enzymes play a major role in the body chemically digesting substances consumed by the body. Enzymes serve as a catalyst and initiate certain chemical processes in regards to particular substances while it not being altered in the process. Namely, amylase, which is present in saliva, converts starches into sugar, thus helping to initiate digestion. Where as there is the enzyme pepsin, which is present in gastric juices in the stomach that helps to break down proteins. On the other hand there is also the enzyme lipase that aids in the digestion in fats. Enzymes play a

very vital role in the chemical digestion of food and ultimately in the body being able to optimally absorbing nutrients from digested food.

On the flipside if the body lacks certain enzymes or cannot produce enough enzymes this can cause a myriad of digestion problems. For example, being lactose intolerant is directly linked to having a lack of lactase causing diarrhea and stomach discomfort and thus, lactose cannot be digested in the small intestines. Celiac disease is also a condition where the body's inability to hydrolyze wheat proteins cause inflammation in the intestines (Mamadou, 2013). In addition, a lot of food allergies can be linked to insufficient digestive enzyme function in the gut and as a result some substances can induce an immune reaction that could be severe (Mamadou, 2013). In this particular lab we will examine the characteristics of amylase, pepsin, and lipase and it effect of certain substance that are ingested by the body.

Materials and Methods Pepsin Digestion

In order to examine the properties of pepsin digestion of proteins 5 cubes of egg white rich in the protein ovalbumin are place in 5 different test tubes. The first test tube was a combination of egg white and 2 ml of warm water. Test tubes 2, 3, and 4 had 2 ml of pepsin and 2 drops of hydrochloric acid were added to only test tubes 2 and 4. In the 5th test tube 2 ml of amylase solution is solely placed with the cube of egg white. Afterwards all 5 tubes are incubated for the duration of 30 minutes. Test tube 2 was incubated at room temperature where as the rest of the test tubes were incubated in warm water. Then the test tubes are shaken and observed if indeed any egg white protein is visible.

Starch Digestion of Salivary Amylase In order to test the presence of starch an iodine solution is added to one test

tube containing starch and another test tube containing only water. Depending upon the color present it will indicate if starch is indeed present in the test tube. After establishing the presence of starch two test tubes are then filled with water starch and iodine solution however the enzyme amylase is added to one of the test tubes. The test tubes are then placed in a beaker of warm water and observed. Then a 3rd test tube is filled with Benedict solution and the solution containing the digested starch is added to the test tube to see if a precipitate will be formed thus testing the presence of simple sugars.

Effect of temperature on digestion of starch by amylase 5 beakers are filled with water and heated at varying degrees ranging from 20,

40,50, 60 and 80 degrees. Then 5 test tubes are filled with 5 ml of starch and labeled to each corresponding beaker based off of temperature. Then 5 test tubes are filled with 5 ml amylase solution and also labeled by temperature corresponding with the heated beakers. Afterwards each test tube containing starch and amylase is placed in pairs in their corresponding beakers for 5 minutes. Then the test tubes based off of temperature with amylase and starch are mixed together. In a tray with iodine solution the mixture is dropped every 30 seconds until there is no change in color. This same procedure is done for all the remaining tubes based off of their corresponding temperature.

Lipid digestion of fat A lipid cream with a pH indicator, which is pink, is added to 4 test tubes.

Water and bile salts are added to the first test tube. Lipase from a pancreatic extract is added to test tube 2. Lipase and bile salt is added to test tube 3. Solely amylase is added to test tube 4. Afterwards the test tubes are observed in order to see if there is change in color/pH which would exhibit whether the lipids are digested or not.

Results

Pepsin Digestion of Protein

# Egg Water Pepsin Hydrochloric Amylase Room Visible

white

acid

Temp Suspension

1 Yes Yes No

No

2 Yes No Yes Yes

3 Yes No Yes No

4 Yes No Yes Yes

5 Yes No No

No

No

Warm No

No

Cold Yes

No

Warm Yes

No

Warm Yes

Yes

Warm No

In the pepsin experiment tubes 1 and 5 did not have visible suspension indicating there was no digestion of protein. Suggesting that solely water or amylase cannot digest protein. On the other hand there is some digestion in tubes 2,3, and 4 based of the fact there was visible suspension. Furthermore, test tube 4 has greater digestion illustrating the fact that enzymes work at an optimal warm temperature versus cold temperature.

Test Starch tube present

Test Yes tube-1 Test Yes tube-2

Iodine present

Yes

Yes

Amylase present

No

Yes

Color of solution after being heated Dark purple

Clear

Mixed with benedict

No

Yes

Digestion of Starch In the digestion of starch experiment both test tubes contained starch and

iodine however the test tube containing the enzyme amylase turned clear after heating. Since the test tube turned clear it reflected that the starch had been broken down. In order to confirm the starch had been broken down Benedict solution was added and as a result precipitate became present. This illustrates that indeed the starch was broken down in to simple sugars.

Test tube #

1 2 3 4 5

Amylase and starch present Yes Yes Yes Yes Yes

Temperature of water

20 degrees 40 degrees 50 degrees 60 degrees 80 degrees

Time until no reaction occurred

2min 1 min 30 sec 1min 30 sec 30 sec

Effect of Temperature on Digestion In testing the temperature in digestion all 5 test tubes contained a combination of amylase and starch however based off of the temperature the speed of digestion was greatly influenced. Based off of time there was a gradient from black, dark brown, to yellow. As a result this illustrated a clear relationship between digestion and temperature.

Lipid Digestion

Test Tube

1

Lipid Cream present Yes

2

Yes

3

Yes

4

Yes

Bile salt Water present present

Yes

Yes

No

No

Yes

No

No

No

Lipase Present

No

Yes Yes

No

Amylase

No No No Yes

Chemical reaction

Stayed pink Light pink Light yellow Stayed pink

In the lipid experiment if lipid fat is digested then it will produce fatty acids, which will alter the pH of the solution and change the solution's color from pink to yellow or white. In tubes 1 and 4 there was no reaction, which illustrates that, neither water nor amylase alone can breakdown lipids. In tubes 2 and 3 there was a chemical reaction. Tube 2 had a slight chemical reaction since it turned light pink however in tube 3 had the greatest chemical reaction and turn light yellow. This shows that lipase works better in conjunction with bile salts.

Conclusion The following experiments were carried out in order to explore the chemical

digestion of the body. In chemical digestion many reactions take place to break down food. The body uses enzymes in order for the body to break down food so the body can absorb vitamins, minerals, and nutrients more efficiently. For instance, in the pepsin experiment the digestion of protein was examined. Upon observation we can assume there was digestion in tubes 2,3, and 4 based of the fact there was visible suspension. Yet in test tube 4 there was greater digestion because enzymes work optimally in warm temperature versus cold temperature.

Looking at digestion of starch we used the enzyme amylase, both test tubes contained starch and iodine however the test tube containing amylase became clear after heating. Based off the test tube turning clear we know the starch had been broken down. When Benedict solution was added it caused a precipitate to form, which verified that, the starch had broken down in to simple simples by the enzyme amylase.

When examining the effects of temperature on digestion we analyzed 5 test tubes containing a combination of amylase and starch at different temperatures and the speed of digestion was greatly affected. There was a clear relationship between digestion and temperature because based off of time there seemed to be a gradient of color from black, dark brown, to yellow, to clear.

Finally in the lipid experiment test tube 1 served as the control group. Test tube 4 showed that amylase can not digest lipids. Test tube 3 and tube 4 showed that lipases does breakdown fatty acids however tube 3 show that bile salts emulsify lipids from large droplets to smaller droplets so that the enzyme can access more lipid molecules and as a result lipids are broken down more efficiently. Ultimately, the experiments conveyed that in order to properly digest food it is imperative to have a good balance of particular enzymes to break down certain food so the body can absorb vital nutrients to maintain homeostasis.

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download