Enzymes Objectives Measure the effects of changes in temperature, pH, and enzyme concentration on reaction rates of an enzyme Explain how environmental factors affect the rate of enzyme-catalyzed reactions. What would happen to your cells if they made a poisonous chemical? You might think that they would die. In fact, your cells are always making poisonous chemicals.
You are to become his research assisitants and help him carry out a research investigation into the properties of microbes. He wants you, his research assistants, to try growing these microbe under a number of different environmental conditions and find out how fast they reproduce.
This investigation involves a determination of the effect of hydrogen ion concentration pH on the growth of microbial cultures. Background Microbes, even if they are supplied with all the necessary nutritional requirements, still may not grow.
Bacteria, single celled eukaryotes and other microbes, can only live and reproduce within a certain range of environmental conditions. Factors that can influence if or how microbes can grow are temperature, pH, dissolved gases, osmotic pressure and water availability.
Microbes, such as bacteria are sensitive to the hydrogen ion concentration they find in their environment.
Large proteins, such as enzymes, are affected by pH. Their shape changes they denature and the very often brings about an alteration of the ionic charges on the molecule. Usually, the catalytic properties of the enzymes are lost and metabolism is halted.
Such acid loving microbes are called acidophiles. Even though they can live in very acid environments, their internal pH is much closer to neutral values. Some bacteria produce acid as they grow. This acid is excreted and lowers the pH or the surrounding environment.
This eventually brings bacterial growth to a halt unless something else in the environment neutralizes the bacterial acid.
When grown in broth, a buffering agent can be used to mop up the excess acid, and keep the pH of the growing culture at optimum values. Each species of microbe has its own characteristic range of pH values in which it grows and reproduces best.
Tools of the Trade In these investigations, a tiny group of each microbe species are placed into a liquid, nutrient filled broth that has been sterilized so no other bacteria will compete!
Usually this is in a special flask called an "Erlenmeyer flask"which is slowly shaken to keep the microbes and nutrient at uniform distributions.
Each growing culture is carefully buffered at the appropriate, and constant, pH for the length of the experiment. At regular intervals of time, small samples of the growing culture are taken from the flask and all reproduction of the microbes stopped by some poison or inhibitor they can also be chilled or frozen.
The size of the population at each time point is then determined. Mendel's Mother shows you -- how bacteria grow.Investigation on the effect of pH on enzymes Essay Sample. Design Experiment.
How does pH of potatoes affect the breakdown of starch by the enzyme Salivary Amylase? Enzymes are proteins that are found inside our bodies and their roles are to break down large molecules into smaller soluble ones.
Investigating the effect of pH on the activity of the enzyme catalase. Introduction Hydrogen peroxide (H2O2) is a very pale blue liquid which appears colourless in a .
Measure the effects of changes in temperature, pH, and enzyme concentration on reaction rates of an enzyme catalyzed reaction in a controlled experiment. Explain how environmental factors affect the rate of enzyme-catalyzed reactions. Investigating the effect of pH on amylase activity Class practical Measure the time taken for amylase to completely break down starch, by withdrawing samples at 10 second intervals and noting the time at which the solution no longer gives a blue-black colour with iodine solution (but the iodine solution remains orange). Investigating the Effect of Ph on the Activity of the Enzyme Catalase. Words | 17 Pages Investigating the effect of pH on the activity of the enzyme catalase.
Investigating the Effect of Ph on the Activity of the Enzyme Catalase. Words | 17 Pages Investigating the effect of pH on the activity of the enzyme catalase. When the pH drops below pH phenolphthalein goes colourless.
Investigating effect of temperature on the activity of lipase | Nuffield Foundation Class practical Phenolphthalein is an indicator that is pink in alkaline solutions of about pH Investigating the effect of pH on amylase activity Measure the time taken for amylase to completely break down a sample of starch, using buffers for different pHs.
Investigating effect of concentration on the activity of trypsin. - Investigating Enzyme Activity Aim: To investigate how the concentration of hydrogen peroxide effects the rate of reaction of an enzyme (catalase) Variables: These factors could effect the rate of reaction on an enzyme: · pH · Concentration · Temperature · Surface Area pH - Enzymes function at different pH values.