Lab Report Essay example

b) Benedict test the solution color will change from blue to pink/orange red, indicating simple sugars are present. Lugols test the solution color will change from yellowish brown to dark purple, indicating starch and polysaccharides are present. Sudan iV test the lipid content will turn into red, indicating lipids are

4. There are other types of reagents used to determine what type of biomolecule a substance is. For example, copper ions present in Benedict’s reagent reacts with the free end of any reducing sugars, such as glucose, when heated. Originally blue in color, these copper ions are reduced by the sugar, and produce an orange-red colored precipitate. Alternatively, iodine-potassium iodide (IKI) may also be used when working with starch. IKI contains special tri-iodine ions which interact with the coiled structure of a starch

When the pH is not at its optimum, the differing pH's will disrupt the bonding between the R groups of the amino acid causing its structure and the shape of the activation site to change

Table 1 Concentration of protein, DNA, and ratio of the two in heart, kidney and liver of bos taurus. Average standard deviation of protein concentration is also shown.

The purpose of this lab was to test different substances using various procedures to see what biomolecules were present and ultimately find out what restaurant Anna Lyza had eaten at before she died. For the first control test, we used vegetable oil to test for lipids. So, if the solution does not contain lipids, it does not become translucent when placed onto a paper bag square and held up to a light. So, it is a negative result. However, in the presence of lipids, the solution will become translucent when placed onto a paper bag square and held up to a light. Therefore in this case, the result is positive. On the other hand, we used albumin egg to test for proteins in another control test. If the solution does not contain proteins, it will not experience any color change and so it is a negative result. When there are proteins existing in the solution, it will turn bluish/purplish and for this reason it is a positive result. Furthermore in the third control test, we used dextrose to test for simple carbohydrates such as glucose. If the solution does not contain simple carbohydrates, it will not undergo any color change and will remain a blue color. So, it is a negative result in this circumstance. If there are simple carbohydrates present in the solution, the solution will turn reddish and so the result is positive. For the last control test, we used starch solution to test

Typically an ionic bond occurs between one metal and one non-metal ion. One atom borrows one or more electrons from another atom. An ionic bond is a type of chemical bond that occurs when one atom loses an electron to form a positive ion and the other atom gains an electron to form a negative ion, which then result in attraction.

The purpose of the lab was to determine the ratio of air to acetylene results in complete combustion of acetylene gas. The balanced chemical equation for this experiment was C2H2(g) + O2(g) --> CO2(g)+ H2O(l). Complete combustion is the reaction of an element or compound with oxygen to produce the most common oxides and energy. Complete combustion occurs when the fuel and oxygen combine in exact proportions to completely burn the fuel, which leaves a clean test tube. Incomplete combustion is the reaction of an element or compound with oxygen to produce some oxides with less oxygen than the most common oxides. Incomplete combustion occurs when there is not enough oxygen to react

This experiment consisted of setting up a control group of starch in various temperature and then placing both fungal amylases and bacterial amylases in a mixture of starch and placing the solution of amylase and starch in various temperatures of water. After a certain amount of time- different amount of time needs to be used in order to have reliable results- iodine is added in a well on spot plates, then two drops of the mixture of amylase-starch is added from each temperature used, by adding iodine into the plates the mixture will show how much starch was hydrolyzed, this is used to calculate the amount of

For this experiment, we have to prepare our phosphorylase which extracted from a potato. We prepared by weighed about 250 grams of peeled potato and cut it into cubes. The extracts then blended with 100mL of 0.1M NaF. After filtered the contents into a clean 250mL centrifuge bottle, we centrifuged it for 3 minutes. Then, separated the supernatant into a centrifuge bottle, which is our phosphorylase preparation. The enzyme assay used in this experiment today is the iodine test. As the iodine reacts with starch, it will form a brown, blue or black precipitate due to the iodine ions forcing into a linear arrangement. The endpoint of the enzyme reaction indicates the presence of starch by using the iodine test to determine. The faster the endpoint is reached, the less active the phosphorylase is.

A cell, the building block of all living organisms, is composed of four fundamental biomolecules: proteins, carbohydrates, sugars and lipids. Proteins provide a vast amount of functions cells such as they serve as enzymes, provide structural support to cells, and act as antibodies. Reagents are used to spark a chemical reaction. The reagent used to detect protein traces in a substance is Biuret’s. Biuret’s will turn purple if proteins are present and blue if they are none. Biuret’s copper particles, have a charge of +2, are diminished to a charge of +1 when peptide bonds, which are in proteins, are present, creating the color change. Polysaccharides, which are carbohydrates, are most notably known to provide energy to the body, but they also help in breaking down fatty acids. Iodine is the reagent used to determine whether a substance has starch in it. The iodine/starch complex has energy levels that are only for retaining unmistakable light, giving the complex its extraordinarily dark black-blue shade. If there is no starch found, iodine will remain its natural yellowish-brownish color, but if starch is present, iodine will turn blue-black. Monosaccharides, which are sugars, like polysaccharides, provide the body with energy. To detect monosaccharides, the reagent, Benedict’s, is used. Benedict’s reagent is added to a test tube, then it is placed in

Record observations: what color did the solution turn? Orange or blue/ black? This will tell whether the amylase is able to denature the starch solution Orange=Negative Blue/black= Positive

groups. It was conducted to further the research in choice overload and paralysis of the mind.

3 drops of Lugol’s solution is added to each tube. Presence of starch is indicated by dark purple color occurrences. The amount of starch is indicated by the shades of reddish brown.

The students first prepared to construct a standard curve. To do this, each group measured the absorbance of starch solutions of unknown concentrations treated with IKI (General Biology I, Martineau, Dean, Gilliland, & Soderstrom, Lab Manual, 2017, 45). The absorbance values were determined for a range of samples, and plotted on a graph. A line of best fit was then used as a reference to determine the amount of starch present in unknown samples.

The iodine test is used to identify glycogen and starch. These polysaccharides combine with iodine to