Part 1 Inaccurate liver sample sizes and finger contact The first error that was problematic in ascertaining accurate results in part 1 was the inability to cut identical 1cm3 pieces of liver.
Practically all of the numerous and complex biochemical reactions that take place in animals, plants, and microorganisms are regulated by enzymes. These catalytic proteins are efficient and specific—that is, they accelerate the rate of one kind of chemical reaction of one type of compound,… The biological processes that occur within all living organisms are chemical reactionsand most are regulated by enzymes.
Without enzymes, many of these reactions would not take place at a perceptible rate. Enzymes catalyze all aspects of cell metabolism. This includes the digestion of food, in which large nutrient molecules such as proteinscarbohydratesand fats are broken down into smaller molecules; the conservation and transformation of chemical energy ; and the construction of cellular macromolecules from smaller precursors.
Many inherited human diseases, such as albinism and phenylketonuriaresult from a deficiency of a particular enzyme.
Enzymes also have valuable industrial and medical applications. The fermenting of wine, leavening of bread, curdling of cheeseand brewing of beer have been practiced from earliest times, but not until the 19th century were these reactions understood to be the result of the catalytic activity of enzymes.
Since then, enzymes have assumed an increasing importance in industrial processes that involve organic chemical reactions. The uses of enzymes in medicine include killing disease-causing microorganisms, promoting wound healing, and diagnosing certain diseases.
Chemical nature All enzymes were once thought to be proteins, but since the s the catalytic ability of certain nucleic acids, called ribozymes or catalytic RNAshas been demonstrated, refuting this axiom.
Because so little is yet known about the enzymatic functioning of RNAthis discussion will focus primarily on protein enzymes. A large protein enzyme molecule is composed of one or more amino acid chains called polypeptide chains.
If the enzyme is subjected to changes, such as fluctuations in temperature or pH, the protein structure may lose its integrity denature and its enzymatic ability. Denaturation is sometimes, but not always, reversible. Bound to some enzymes is an additional chemical component called a cofactorwhich is a direct participant in the catalytic event and thus is required for enzymatic activity.
Investigation into the factors which affect the rate of catalase action. Planning Aim: To investigate the affect of concentration of the enzyme catalase on the decomposition reaction of hydrogen peroxide. The enzyme: Catalase . Abstract. Composition of the culture medium, growth phase, and temperature play important roles in the sensitivity of Escherichia coli to H2O2. The medium and growth phase affected the sensitivity of the cells to H2O2 by modifying the amount of catalase synthesized by them, whereas the effect of temperature was due to the thermolability of the enzyme. LAB: FACTORS INFLUENCING ENZYME ACTIVITY such a molecule increases the rate of the reaction it is an activator, and if it decreases the reaction mix the catalase solution before you pour it into your cup for dipping the disks. 4. Record your data in the table below.
A cofactor may be either a coenzyme —an organic molecule, such as a vitamin —or an inorganic metal ion ; some enzymes require both. A cofactor may be either tightly or loosely bound to the enzyme.
If tightly connected, the cofactor is referred to as a prosthetic group. Nomenclature An enzyme will interact with only one type of substance or group of substances, called the substrateto catalyze a certain kind of reaction. Not all enzymes have been named in this manner, however, and to ease the confusion surrounding enzyme nomenclaturea classification system has been developed based on the type of reaction the enzyme catalyzes.
There are six principal categories and their reactions: Mechanism of enzyme action In most chemical reactions, an energy barrier exists that must be overcome for the reaction to occur.
This barrier prevents complex molecules such as proteins and nucleic acids from spontaneously degrading, and so is necessary for the preservation of life. When metabolic changes are required in a cell, however, certain of these complex molecules must be broken down, and this energy barrier must be surmounted.LAB: FACTORS INFLUENCING ENZYME ACTIVITY such a molecule increases the rate of the reaction it is an activator, and if it decreases the reaction mix the catalase solution before you pour it into your cup for dipping the disks.
4. Record your data in the table below. The purpose of this experiment is to analyze the effect of multiple variables to determine if they have an effect on the rate at which catalase catalyzes H 2 0 2 decomposition.
Such factors include the re-using of the enzyme, increasing its surface area, the effect of temperature or its concentration. In addition to temperature and pH there are other factors, such as ionic strength, which can affect the enzymatic reaction.
Each of these physical and chemical parameters must be considered and optimized in order for an enzymatic reaction to . Factors Affecting Enzyme Activity Abstract: In the following lab factors affecting enzyme activity, temperature, pH, enzyme concentration, The purpose was to isolate catalase and measure the rate of activity under different conditions.
P LANNING Aim: Our aim is to detect which factors affect the rate of the decomposition of hydrogen peroxide with a fixed mass of catalyst. A catalyst is a substance, which alters the speed, or rate of a chemical reaction but is chemically unchanged at the end of the reaction.
There are many factors that contribute to the rate of reaction of an enzyme. Factors include: concentration of the enzyme, temperature, pH level, concentration of the substrate, and inhibitors.
This lab shows the affects these factors have on the rate of reaction between catalase, an enzyme found in potatoes, and hydrogen peroxide, the substrate.