Lab Report 1 Principles of Biology 1(BIOL 100) Fall 2001 Gerard Chretien Living cells perform a multitude of chemical reactions very rapidly because of the participation of enzymes. Enzymes are biological catalysts, compounds that speed up a chemical reaction without being used up or altered in the reaction. The material with which the catalysts reacts, called the substrate, is modified during the reaction to form a new product. But because the enzyme itself emerges from the reaction unchanged and ready to bind with another substrate molecule, a small amount of enzyme can alter a relatively enormous amount of substrate. This report will illustrate the enzymatic action of the enzyme catecholase, which is common in plants. To study this particular enzyme in a laboratory, the natural substrate catechol is oxidized by the removal of two hydrogen atoms. The substrates of the enzyme are catechol and oxygen. These substates react with one another within the active site of the enzyme. The products formed by this reaction are benzoquinone has a brown color, you can see that the reaction has taken place. This is called the fruit browning reaction. Benzoquinone inhibits the growth of microorganisms and prevents damaged fruit from rotting. In undamaged cells catecholase is stored in vesicles and does not interact with catechol. In the presence of the enzyme catecholase: Catechol+1/2O2 benzoquinone+H2O The structure of the enzyme is mainly dependent on the active site and variable groups. Extreme temperatures or extreme pHs can alter the structure of an enzyme. Enzymes function to lower the activation energy to break the bonds. They achieve this by putting stress and pressure on the bonds or creating a microenvironment for the substrate. A change in the temperature or a fluctuation in pH can alter... ... middle of paper ... ... questions and test answers. The method has five stages: 1. Making observation. 2. Asking questions. 3. Forming hypotheses, or tentative answers to the questions. 4. Making predictions based on the hypotheses. 5. Testing the predictions by making additional observations or conducting experiments. The information gained may support or yield opposite results based on predictions being tested. My independent variable would be time and the dependent one would be the enzyme pectinase. I believe the key feature of my experimentation is the control of most factors so that the influence of a single factor can be seen clearly. The setting would take place within a laboratory, equipped with various components such as tubes, microscope and other related equipment. I would try to investigate the physical properties of pectin such as molecular weight, molecular conformation and aggregation of pectin molecules in the solution. In regards to the pulpiness of the applesauce, I would use the pectin as a emulsifier and stabilizer. This procedure would reduce the pulp of the applesauce considerably without making the solution too watery.
Additionally, the most important part of an enzyme is called the active site, this is where molecules bind to the enzyme when the reactions are taking place. Enzymes are very specific and if the shape changes of the active site, this stops the enzyme from functioning. When the temperature is increased significantly it will cause a permanent change to the shape of the active site and the enzymes will stop working, they will become denatured. The bonds which are holding the structure are called intermolecular bonds (e.g hydrogen) are broken easily by heat. Thus when the enzyme is heated, these bonds are broken, the active site specificity is no more, and therefore it becomes denatured and is no longer a functioning catalyst (“Introduction to Enzymes.”).
Enzymes are used to carry out reactions in a rapid manner otherwise the reaction would occur very slowly thus not being able to sustain life. Enzymes bind to a substrate that is specific to their task and then conforms into a product that is needed; the enzyme is then able to catalyze more of the same reaction. Enzymes and substrates act as a lock and a key since enzymes are made for a specific substrate and is able to form an enzyme-substrate complex (Department of Biology). Thus changes of the shape of an enzyme can inhibit its ability to catalyze a reaction. If the enzyme shape is alternated due to environmental conditions, it is denatured and can no longer act as a catalyst. Peroxidase is the type of enzyme used in this
Enzymes are biological catalysts, which are proteins that help speed up chemical reactions. Enzymes use reactants, known as the substrates, and are converted into products. Through this chemical reaction, the enzyme itself is not consumed and can be used over and over again for future chemical reactions, but with the same substrate and product formed. Enzymes usually only convert specific substrates into products. Substrates bind to the region of an enzyme called the active site to form the enzyme/substrate complex. Then this becomes the enzyme/products complex, and then the products leave the enzyme. The activity of enzymes can be altered based on a couple of factors. Factors include pH, temperature and others. These factors, if they become
Jim Clark. (2007). The effect of changing conditions in enzyme catalysis. Retrieved on March 6, 2001, from http://www.chemguide.co.uk/organicprops/aminoacids/enzymes2.html
...e substances at 37.5̊C due to the fact that in the previous experiment, this was found to be the optimum temperature that catalase reacts at. It was because of this constant that I used the set of data of the catalase at 37.5̊C from the first experiment to provide a neutral environment for the experiment. The way in which the data was collected for the first experiment was identical to that needed to be done by the second. From this data, it was determined that the neutral environment for the catalase had the best results, which makes it clear that when the enzyme is in a pH of the opposite extremes such as basic or acidic, it is un able to function properly. When it is too basic then the enzyme will become inactive and when the enzyme is too acidic then the enzyme will denature, both rendering it unable to function at its optimum efficiency that all enzymes need.
During this lab we took a more in depth look at the results of catechol oxidase activity. Biological catalysts that speeds up chemical reactions and are inexhaustible are called enzymes. The substrate is the material that is being acted on by the enzyme. When it comes down to enzymes, they perform better. Enzymes work better due to the fact that they can bind to the change state better than the substrate. As this happens it can lower the beginning energy triggering the speed of a reaction to quicken. Catalysis is very crucial. Catalysis makes chemical reactions occur quicker than they would without any assistant.
Two environmental factors can effect enzyme activity: pH and temperature. Changes in the pH can alter the level of hydrophobicity of some regions of a protein, thus altering its shape. If the enzymes shape is altered then it will not bind with its receptor. Temperature also affects enzyme activity. All enzymes perform best at their optimal temperature. In addition, each enzyme has a minimum and maximum temperature at which it can successfully perform. Substrate concentration can chemically
The model we use to explain how the cell membrane works is called a fluid mosaic model. The Fluid mosaic model was created by S.J Singer and Garth Nicolson in 1972. Between the living machinery of the inner cell and the harsh conditions of the outside world, stands the cells plasma membrane. As crucial as this barrier is, its surprisingly flexible, push it and it will move, poke hard enough and it will break and begin to regroup. We first look at the molecule called phospholipids when thinking about the plasma membrane. Lipids usually have three fatty acid chains, however this molecule has two fatty acid chains. Instead of the third fatty acid chain, a phosphate group is added on. This phosphate group is what makes the phospholipids so special. It is polar and hydrophilic, whereas the rest of the molecule is non-polar and hydrophobic. The hydrophilic heads point outwards as it attracts water molecules, whereas as the hydrophobic tails point inwards due to its mutual attraction and water repulsion. Therefore creating the phospholipid bilayer, which is the basis of all cellular membranes. Throw in some cholesterol and some carbohydrates and you have the basic structure of a plasma membrane. From chemical analysis, we conclude that there are protein in the cell membrane. Using freeze-fracture imaging and scanning electron microscope, we are able to differentiate between the extracellular surface of the membrane and the inside lipid bilayer. Within these lipid molecules, we also find different proteins, which do various things for the cell. For instance, they receive signal from the world outside, and also transport nutrients and waste. So nature composes the membrane with a composition or mosaic of different lipids, carbo...
Our bodies involve and require many different biochemical reactions, which is achieved through the help of enzymes. Enzymes are proteins in our bodies that act as catalyst as they speed up vital biochemical reactions by reducing the “activation energy” needed to get the reaction going. To sustain the biochemistry of life, enzymes maintain temperature inside our living cells balanced and the concentration of reaction molecules. Enzymes are extremely efficient because they remain remarkably unchanged, therefore have the potential to be used over and over again. They are extremely specific with the reactions they catalyze, like a lock and key and, extremely reactive. The molecule to which enzymes make accelerated changes to is the substrate. The molecule that is present after the enzyme-catalyzed reaction is the product. Most enzymes require specific environmental conditions such as temperature and pH levels to be met in order for them to function properly and efficiently. In the first part of the lab we specifically examined a simple enzyme-catalyzed reaction using catechol (the substrate) which will be catalyzed by the enzyme catecholase and will then result in color change. This familiar color
Enzymes are types of proteins that work as a substance to help speed up a chemical reaction (Madar & Windelspecht, 104). There are three factors that help enzyme activity increase in speed. The three factors that speed up the activity of enzymes are concentration, an increase in temperature, and a preferred pH environment. Whether or not the reaction continues to move forward is not up to the enzyme, instead the reaction is dependent on a reaction’s free energy. These enzymatic reactions have reactants referred to as substrates. Enzymes do much more than create substrates; enzymes actually work with the substrate in a reaction (Madar &Windelspecht, 106). For reactions in a cell it is important that a specific enzyme is present during the process. For example, lactase must be able to collaborate with lactose in order to break it down (Madar & Windelspecht, 105).
Fruits contain an enzyme called pectinase that helps to break down the cell wall of a cell. This allows for the DNA of the plant cell to be more easily extracted from the
In this lab, it was determined how the rate of an enzyme-catalyzed reaction is affected by physical factors such as enzyme concentration, temperature, and substrate concentration affect. The question of what factors influence enzyme activity can be answered by the results of peroxidase activity and its relation to temperature and whether or not hydroxylamine causes a reaction change with enzyme activity. An enzyme is a protein produced by a living organism that serves as a biological catalyst. A catalyst is a substance that speeds up the rate of a chemical reaction and does so by lowering the activation energy of a reaction. With that energy reactants are brought together so that products can be formed.
Enzymes are protein molecules that are made by organisms to catalyze reactions. Typically, enzymes speeds up the rate of the reaction within cells. Enzymes are primarily important to living organisms because it helps with metabolism and the digestive system. For example, enzymes can break larger molecules into smaller molecules to help the body absorb the smaller pieces faster. In addition, some enzyme molecules bind molecules together. However, the initial purpose of the enzyme is to speed up reactions for a certain reason because they are “highly selective catalysts” (Castro J. 2014). In other words, an enzyme is a catalyst, which is a substance that increases the rate of a reaction without undergoing changes. Moreover, enzymes work with
The grape and pear fruits were set aside at dark place and room temperature for a few days to allow decaying process. After a few days, the grape and pear were squeezed to obtain the fermented juice of the fruit. Then 1 mL each of the juice was transferred into universal bottle to be diluted until 10-5. While for the dried fruit, the samples were crushed using mortar and pestle. 1 g of crushed sample was weighed and transferred into universal bottle and soaked with 5 mL peptone water to allow fermentation process. Then, 1mL of the dried fruit sample was diluted until 10-5 in the universal