Urea Determination Lab Report

Enzymes are molecules that accelerate the rate of a reaction through the lowering of the activation energy necessary to perform the reaction without their presence. Depending on the environment that the enzyme is in, determines how efficient the enzyme will be in accelerating the reaction. Factors such as pH and temperature play a role on the enzyme’s efficiency and overall success of the reaction. For example, having a high temperature can break apart non-covalent interactions within proteins—the most common form of an enzyme. The breaking down of these bonds would result in the enzyme having a conformational change that does not allow the substrate to fit into its active site. In our experiment, we used the enzyme cellobiase in order to study

0.0375 mg/ml Porcine Pancreatic Amylase Solution (amylase powder in 0.9% NaCl ), Iodine Solution; each solution were pipetted into each of the 5 test tubes with 5 ml of 1% starch. Each tube contained a 1% starch solution with a different pH. All tubes were at room temperature. Room temperature was 22C. 0.2 ml of porcine pancreatic amylase solution was then pipetted into each tube. A timer was started and every 3minutes the starch / amylase mixture were pipetted from each tube and pipetted into the spot plate for every sample tube, then the iodine solution were added to a spot plate cell for each sample. Iodine reacts with starch to change from yellow to deep blue /black in the presence of starch. A lightening of the blue/ black to a brown color will occur as less starch is present. Results were reported as (+) for presence of starch in the sample or (–) for the absence of starch. After every three minute increment had passed, these same

Enzymes are catalysts that function to speed up reactions; for example, the enzyme sucrose speeds up the hydrolysis of sucrose, which breaks down into glucose and fructose. They speed up reactions but are not consumed by the reaction that is taking place. The most important of the enzyme is the shape as it determines which type of reaction the enzyme speeds up. Enzymes work by passing/lowering and energy barrier and in doing so; they need to bind to substrates via the active. Once they do, the reaction speeds up so much more quickly than it would without the enzyme. Coenzymes and cofactors aid the enzyme when it comes to binding with the substrate. They change the shape of the active site so the substrate can bind properly and perform its function.

2. We measured 1 mL of turnip peroxidase (the enzyme) and 3 mL of neutral buffer (pH corresponding to the test tube number i.e. pH 5 in test tube 5) with a syringe and disposed it into tubes 3, 5, 6, 7, 8, and 10

Ionic compounds are soluble in water to a certain point depending on the compound. The level of solubility changes among different compounds. Some ionic compounds can completely dissolve in water and appear to be a homogeneous mixture. Although, some ionic compounds dissolve very little, and could be considered insoluble, since it does not dissolve fully. Depending on the compound, the level of solubility can be high or low. However, ionic compounds could dissolve to a certain degree. If the solution appears to be a heterogeneous mixture, many may assume through visual representation that it may be insoluble. As stated previously, the smallest amount of solubility should be considered. To confirm whether or not the substance is soluble, observe the efficiency when conducting electricity. Due to practical reasons, the slightest solubility could be considered insoluble by people.

For the Urease test, I incoluated my Urea test tube with my unkown bacteria from a TSA plate using and inoculating loop. The Urea tube was then incubated at 37 degrees Celsius for 8 days to observe for a color change. The Urea tests for the ability of a bacteria grown in urea broth produces urease. This medium contains the pH indicator phenol red. If urease is produced the pH of the media will raise thus causing the phenol red to change from yellow to a pink color.

Eisenthal, R. & M.J. Danson (Eds.) (2002). _Enzyme Assays: A Practical Approach_. United Kingdom: Oxford University Press

An experiment was performed to test how temperature variations affect enzymatic activity of the enzyme amylase. The results of the experiment will also determine the optimal temperature of the amylase enzyme. The results of the experiment provide evidence for determining the environments that the enzyme amylase would most likely be present. By determining the possible environments, one can predict what and how environmental factors will affect the enzyme amylase. Two forms of amylase (Bacterial - Bacillus licheniformis and Fungal - Aspergyllus oryzae) were combined with starch molecules at four different temperatures (0⁰, 25⁰, 65⁰, 85⁰ Celsius). The combination of starch and the amylase enzyme resulted in a visual chemical reaction that was recorded. The enzyme activity was recorded every two minutes, starting at 0 and ending at 10. The start time 0 served as the control group of the experiment. The results concluded that both bacterial and fungal amylase has an optimal temperature around 65⁰C. This was possible to determine by recording the color change of the spot plate wells. Amylase catalyzes efficiently at its optimal temperature which resulted in yellow spot plate wells. Enzymatic activity decreased when the temperature was less than 65⁰C, resulting in a green-brown well. The green wells indicated that starch wasn’t broken down completely and was still present. Temperatures greater than 65⁰C resulted dark-green wells which resembled the denaturing of

Urease is an intracellular enzyme that hydrolyzes urea into ammonia and carbon dioxide. Urea broth is used to determine urease production. Phenol red is used as a pH indicator. Urea hydrolysis produces ammonia that raises the pH in the medium and turn pH indicator pink (Leboffe and Pierce). The positive test for urease is pink in color that takes around 8 days.

Enzymes have things called ‘Active Sites’ this the spot where substrates bind and chemical reaction takes place. Each enzyme has a different shape, this allows the enzyme to receive only one type of

| Analysis of urine by physical, chemical, microscopical means to test for the presence of disease drug.

The purpose of this lab experiment was to determine the relationship between temperature and the rate of enzymatic activity in yeast cells. In the lab, the temperature was the independent variable. The temperatures consisted of 6°C, 24°C, 34°C, 46°C. The dependent variable in the experiment was the rate of enzymatic activity in yeast cells. The temperatures were tested by using a LabQuest and pressure probe that tested pressure inside the plastic test tube. LabQuest graphed the data and created a line of best fit that was used to determine the slope of the graph. The slope of the graph represents the rate of enzymatic activity. The slope was found for each temperature in 2 different trials. Then, the rate of enzyme activity (kPa/sec) for each temperature in the 2 trials were averaged. These averages were used to develop a graph that shows the relationship between temperature and the rate of enzyme activity. According to the results of the experiment, as the temperature increases, the rate of enzymatic activity decreases. Each enzyme has its own optimal temperature in which it can function efficiently.

Organisms cannot depend solely on spontaneous reactions for the production of materials because they occur slowly and are not responsive to the organism's needs (Martineau, Dean, et al, Laboratory Manual, 43). In order to speed up the reaction process, cells use enzymes as biological catalysts. Enzymes are able to speed up the reaction through lowering activation energy. Additionally, enzymes facilitate reactions without being consumed (manual,43). Each enzyme acts on a specific molecule or set of molecules referred to as the enzyme's substrate and the results of this reaction are called products (manual 43). As a result, enzymes promote a reaction so that substrates are converted into products on a faster pace (manual 43). Most enzymes are proteins whose structure is determined by its sequence of its amino acids. Enzymes are designed to function the best under physiological conditions of PH and temperature. Any change of these variables that change the conformation of the enzyme will destroy or enhance enzyme activity(manual, 43).

Seeing how the results of each urine sample do not match the characteristics of healthy urine, it should be noted that all samples tested throughout the lab experiment each contain problems caused by diseases existing in the kidneys. To start, sample W comprises of one common scenario that indicates the presence of a kidney condition - that is the high concentrations of the macromolecule glucose that were found. When significant amounts of glucose are detected in urinalysis, it is most likely that the individual has a case of diabetes, notably type 1 and type 2. Complications arise when excessive amounts of glucose take up the liver. To illustrate, due to the large size of the glucose molecule, in comparison to other molecules that the kidneys filter, it harms the

How does decreasing the levels of pH by adding Hydrochloric acid affect the Amylase’s ability to break down potato starch solution?