An important but commonly overlooked aspect of image-based assay design for high content analysis (HCA) is the use of appropriate controls. Table 8.3: Effect of concentration on enzyme activity.Having sufficient replicates is not enough to ensure reliable results. Measure the height of the bubble column (in millimeters) and record your observations in Table 8.3.ĭo the data support or contradict your hypothesis?.Swirl well to mix and wait at least 20 seconds. The height of the bubbles above the solution will be our measure of enzyme activity (Figure 8.2).īefore you begin with the actual experiment, write down in your own words the hypothesis for this experiment: When catalase is added to hydrogen peroxide, the reaction will take place and the oxygen produced will lead to the formation of bubbles in the solution. Hydrogen peroxide will not spontaneously degrade at room temperature in the absence of enzyme. The first experiment will establish that our catalase works (positive control) and that our reagents are not contaminated (negative control). In these experiments, we will use catalase enzyme from potato. Cells therefore use catalase to protect themselves. Catalase speeds up the following reaction: In this laboratory, we will study the effect of temperature, concentration and pH and on the activity of the enzyme catalase. Some household products use enzymes to speed up chemical reactions: enzymes in biological washing powders break down protein, starch or fat stains on clothes, and enzymes in meat tenderizer break down proteins into smaller molecules, making the meat easier to chew. Some enzymes are used commercially, for example, in the synthesis of antibiotics. An enzyme’s activity decreases markedly outside its optimal temperature and pH. Many therapeutic drugs and poisons are enzyme inhibitors. Enzyme activity can be affected by other molecules: inhibitors are molecules that decrease enzyme activity, and activators are molecules that increase activity. Enzymes differ from most other catalysts by being much more specific. Chemically, enzymes are like any catalyst and are not consumed in chemical reactions, nor do they alter the equilibrium of a reaction. An extreme example is orotidine 5’-phosphate decarboxylase, which allows a reaction that would otherwise take millions of years to occur in milliseconds. Some enzymes can make their conversion of substrate to product occur many millions of times faster. Like all catalysts, enzymes increase the reaction rate by lowering its activation energy. Enzymes’ specificity comes from their unique three-dimensional structures. Most enzymes are proteins, although a few are catalytic RNA molecules. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Metabolic pathways depend upon enzymes to catalyze individual steps. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. The molecules upon which enzymes may act are called substrates and the enzyme converts the substrates into different molecules known as products. 14.2.23 Fucus male conceptacle (Figure 14.2.24 Fucus female conceptacle (Figure 14.2.25 PolysiphoniaĮnzymes are macromolecular biological catalysts.14.2.14 Mixed green algae (Figure 14.2.15 Chlamydomonas (Figure 14.2.16 Pandorina (Figure 14.2.17 Volvox (Figure 14.2.18 Volvox sexual stages (Figure 14.2.19 Spirogyra (Figure 14.2.20 Oedogonium zoospores (Figure 14.2.21 Oedogonium macrandous (Figure 14.2.22 Fucus male and female conceptacle.14.2.12 Trypanosoma cruzi and Trypanosoma brucei gambiense.14.2.1 Amoeba proteus (Figure 14.2.2 Paramecium 4 types of protista (Figure 14.2.3 Paramecium caudatum (Figure 14.2.4 Paramecium in conjugation (Figure 14.2.5 Euglena (Figure 14.2.6 Dinoflagellate (Figure 14.2.7 Ceratium (Figure 14.2.8 Peridinium (Figure 14.2.9 Foraminifera.13.4.7 Oscillatoria (Figure 13.4.8 Nostoc (Figure 13.4.9 Anabaena.13.4.1 Mixed coccus (Gram stain) (Figure 13.4.2 Mixed bacillus (Gram stain) (Figure 13.4.3 Spirillum.12.5 Visualizing the DNA fragments from the restriction digest.12.4 Loading the DNA samples on the agarose gel and agarose gel electrophoresis.12.3 Setting up the restriction digest reactions. 12.2 Preparing a gel for agarose gel electrophoresis.10.2 Preparing an Onion root tip squash.9.3 Determination of the light absorption spectrum of dye solutions.8.4 Effect of pH on enzyme activity (Experiment 4).8.3 Effect of concentration on enzyme activity (Experiment 3).8.2 Effect of temperature on enzyme activity (Experiment 2).8.1 Positive and negative controls (Experiment 1).7.8 Crenation and Hemolysis of Red Blood Cells.7.5 Diffusion Through a Selectively Permeable Membrane.7 Exchange Between Cells and Their Environment.5.7 Test for organic and inorganic compounds (Demonstration).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |