... Enzymes are also sensitive to pH, different enzymes have different pH optimums which are determined by their surroundings e.g. pepsin found in the stomach has an optimum of around pH 2 as the stomach is a very acidic part of ...

... present abundantly in all living cells, and must play an important part in the metabolism of the cell. For example, the plasma membrane allows the movement of several substances into and out of the cell. The following diagram shows the substances that ...

... should be cleaned away in an adequate way. This will prevent accidents in lab rooms. Method> Place all needed equipment as shown in the diagram> Make a starch solution which consists of 4 ml of starch and 6 ml of water ...

... factors that I have found affect the permeability of cell membranes, must somehow destroy part of the cell membrane to allow the pigment molecules to get through and make the surrounding water turn red. (Sources of information: www.fed.cuhk.edu.hk/~johnson/tas/investigation/membrane_teacher.htm C.A.D Discussion ...

... splitting of peptide bonds on the carboxyl side of lysine and arginine residues. Therefore the exclusion of trypsin will reduce dramatically the activity of other proteases. It works best at a slightly alkaline pH (pH 7.6-8). This pH is created ...

... are specific, this means that each enzyme catalyses a certain chemical reaction. An enzyme has an active site, which has a unique shape into which only a substrate of same unique shape can be fit. When this substrate fits into ...

... certain conditions. It can be denatured in high phs and high temperatures. The bonds, which hold the enzyme together, are fairly weak, so they can be easily broken. Once the bonds of the enzyme break, the enzymes active site begins ...

... be controlled by using syringes that are accurate to the measurements being used i.e. the smallest syringe for the measurement. For example, I will be measuring 5cm³ of diastase so the most accurate syringe I could use is a 5cm³ ...

... able to obtain a fairly strong conclusion. Finally, I will evaluate my experiment and results commenting on any errors observed, and what improvements can be made to make the experiment more accurate. Prediction I predict that as the concentration decreases ...

... an optimum temperature at which it works best at. Enzymes are thought to work according to lock and key theory, as enzyme has to fit exactly to substrate. This idea can also be linked to the collision theory, as the enzyme weakens ...

... blocks into cubes of 1cm3, 2cm3 and 3cm3 on a white tile. The same shape blocks (cubes) must be used so that it is a fair test. Accurately measuring and cutting them with the metric ruler and knife. The same ...

... paper over) A hypothesis for this experiment would predict a significant increase in fruit juice extraction using cellulase. Since the hypothesis predicts a change in the dependent variable as the independent variable changes, the appropriate graphical treatment of the data was ...

... released the most oxygen. We also found that the best amount of yeast to use is 0.5g Planning The aim of this investigation is to find out the rate of reaction of catalase on H2O2. The variable I am going to ...

... the temperature to 30, 35 and 40?c, this is where I will see the greatest reaction. I predict this because enzymes are designed to work best at the internal body temperatures of the animals they belong to. For a mammal, ...

... Enzymes Enzymes are biological catalysts made up from protein that control vital biological processes. As we know catalysts are substances that speed up a rate of a reaction without itself being used up. An enzyme has an active site, which has ...

... as those which take place in the metabolism. Typically, an enzyme is a large protein that consists of a folded chain of hundreds of amino acids. Each enzyme binds to a specific molecule and stresses the bond of that molecule ...

... different parts of the chain. Hydrogen bonds, disulphide bonds between the cysteine molecules (which is an amino acids that contains sulphur, C3H7NO2S), ionic bonds between ionised amine and carboxylic groups and van der Waals interactions between non-polar side chains keeping ...

... pH may also change the charge on the R groups, decreasing the affinity between substrate and the active site. Enzymes are globular proteins. Enzymes lo9wer the activation energy barrier of an reaction making it possible for more molecules to react ...

... The temperature of the water in the water bath was taken using a thermometer. It was 26?C. A water bath was used so that the temperature would be the same for all the pHs because the temperature of the laboratory varies. Then ...

... Room temperature investigations were also carried out (20 degrees). Using a Bunsen burner, tripod and beaker of water 100 degrees could also be tested and 0 degrees was tested by using ice. (I didn't investigate the 80 degrees temperature). Fair test: Below ...

... these reactions would occur too slowly or not at all, and no life would be possible. All living cells make enzymes, but enzymes are not alive. Enzyme molecules function by altering other molecules. Enzymes combine with the altered molecules to ...

... Since the kinetic energy increases , the velocity of particles will also increase. Since the speed of particles increases, they should collide more often and therefore the speed of reaction increases. The particles will also have more energy thereby speeding ...

... can a.) Break down large molecules into smaller ones which are much easily absorbed by the body and these enzymes are usually called "breaker" enzymes. b.) Join small molecules together to form large molecules that are used inside the body's cells. These ...

... several broad categories, such as hydrolytic, oxidising, and reducing, depending on the type of reaction they control. Hydrolytic enzymes accelerate reactions in which a substance is broken down into simpler compounds through reaction with water molecules. Oxidising enzymes, known as ...

... with 10cm hydrogen peroxide from the water bath. 7.Take the first conical flask containing the celery extract; arrange the apparatus as above and empty the syringe into the flask closing the 3-way tap start the stopwatch. 8.Measure the volume of oxygen released ...