Investigating a Factor that Affects Enzyme Activity
Planning
--------
Aim
---
To investigate a factor which will affect the activity of catalase,
whilst keeping all variables constant.
Possible Independent Variables
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Here are a number of possible independent variables that could be
changed in the experiment:
Independent variable
Continuous/Discontinuous
Easy to measure?
Volume of substrate used
Continuous
Yes
Type of enzyme
Discontinuous
Yes
Overall mass of piece of meat
Continuous
No
Type of substrate used
Discontinuous
Yes
Temperature of substrate
Continuous
Yes
pH of substrate
Continuous
No
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Concentration of substrate used
Continuous
Yes
The independent variable I have chosen, or the one to be changed
throughout the experiment will be 'the concentration of substrate
used', which will range from 0.25M to 1.25M with increments of 0.25M.
With reference to the table above, it has been chosen, as it is
continuous (i.e. it has a numerical value of some sort and this can be
altered) so the results can facilitate a graph.
Dependent Variable
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Rate at which the bubbles of oxygen rise, which will be calculated by
observing how many bubbles of oxygen rise to the surface of a
measuring cylinder (by means of downward displacement) in one minute.
This will be measured in bubbles per ten seconds.
Control variables:
¨ Volume of substrate used: 100ml
¨ Temperature: taken place at room temperature 21 degrees centigrade
¨ Type of substrate used: Hydrogen peroxide
¨ Mass of meat used: 5g
¨ Amount of water in the test tube in which the oxygen bubbles
downward displaces in the water. This is so the time taken for each
individual bubble to effectively rise to the bottom of the test tube
will take the same amount of time.
Data table 1 Well plate Contents Glucose concentration A 3 drops 5% sucrose + 3 drops distilled water Negative B 3 drops milk+3 drops distilled water Negative C 3 drops 5% sucrose +3 drops lactase Negative D 3 drops milk +3 drops lactase 15+ E 3 drops 20% glucose +3 drops distilled water 110 ++ Questions B. In this exercise, five reactions were performed. Of those reactions, two were negative controls and one was a positive control.
For example, substrate concentration, enzyme concentration, and temperature could all be factors that affected the chemical reactions in our experiment. The concentration of substrate, in this case, would not have an affect on how the bovine liver catalase and the yeast would react. The reason why is because in both instances, the substrate (hydrogen peroxide) concentration was 1.5%. Therefore, the hydrogen peroxide would saturate the enzyme and produce the maximum rate of the chemical reaction. The other factor that could affect the rate of reaction is enzyme concentration. Evidently, higher concentrations of catalase in the bovine liver produced faster reactions, and the opposite occurs for lower concentrations of catalase. More enzymes in the catalase solution would collide with the hydrogen peroxide substrate. However, the yeast would react slower than the 400 U/mL solution, but faster than the 40 U/mL. Based on this evidence, I would conclude that the yeast has a higher enzyme concentration than 40 U/mL, but lower than 400
Abstract: Enzymes are catalysts therefore we can state that they work to start a reaction or speed it up. The chemical transformed due to the enzyme (catalase) is known as the substrate. In this lab the chemical used was hydrogen peroxide because it can be broken down by catalase. The substrate in this lab would be hydrogen peroxide and the enzymes used will be catalase which is found in both potatoes and liver. This substrate will fill the active sites on the enzyme and the reaction will vary based on the concentration of both and the different factors in the experiment. Students placed either liver or potatoes in test tubes with the substrate and observed them at different temperatures as well as with different concentrations of the substrate. Upon reviewing observations, it can be concluded that liver contains the greater amount of catalase as its rates of reaction were greater than that of the potato.
The independent variable for this experiment is the enzyme concentration, and the range chosen is from 1% to 5% with the measurements of 1, 2, 4, and 5%. The dependant variable to be measured is the absorbance of the absorbance of the solution within a colorimeter, Equipments: Iodine solution: used to test for present of starch - Amylase solution - 1% starch solution - 1 pipette - 3 syringes - 8 test tubes – Stop clock - Water bath at 37oc - Distilled water- colorimeter Method: = == ==
Dependent variable: We are measuring the time taken for the pink indicator to turn clear when hydrochloric acid is added to it. Independent variable: We are changing the molar of hydrochloric acid we are adding to the gelatine cubes. The molars range from 1-3.
Investigating the Effect of Substrate Concentration on Catalase Reaction. Planning -Aim : The aim of the experiment is to examine how the concentration of the substrate (Hydrogen Peroxide, H2O2) affects the rate of reaction. the enzyme (catalase).
I have chosen to vary the concentration of the enzyme catalase, as it is simple to do in the laboratory, and will obtain easy to interpret results. Therefore, all the other variables will be kept constant to make sure the experiment is fair. Keeping the experiment fair: All of the variables with the exception of the concentration of catalase will remain the same, to make sure that the results obtained are not influenced by anything other than the concentration.
I predict that if I double the amount of yeast then I will get double the amount of oxygen produced because I am doubling the rate of which the particles collide. I predict that if I double the amount of water in the yeast then the oxygen will have decreased by double because I am halving the amount of yeast particles the can react. Independent Variable = ==
The input variables are the ones that I can change in order to affect the experiment and the outcome variables are the ones I will measure to see how the input variable has affected it. Input Variables --------------- Amount of calcium carbonate Amount of hydrochloric acid Surface area of calcium carbonate Concentration of hydrochloric acid Temperature of hydrochloric acid Introduction of a catalyst Outcome variables ----------------- Amount of calcium chloride released Amount of water released Amount of carbon dioxide released Change in weight
Investigating the Effect of Enzyme Concentration on the Hydrolysis of Starch with Amylase Aim: Investigate the effect of enzyme concentration on the rate of an enzyme-controlled reaction. Using amylase and starch as my example. Introduction: I am investigating the effect of the concentration of the enzyme, amylase on the time taken for the enzyme to fully breakdown the substrate, starch to a sugar solution. The varied variable will be the concentration and all other variables are going to be fixed. The different concentrations will be: 0.5% 0.75% 1.0% 1.5% 2% An enzyme is a class of protein, which acts as a biological catalyst to speed up the rate of reaction with its substrates.
All times were recorded in the table under the appropriate label. Each substance had a Time 1, Time 2 and Time 3 (T1, T2, and T3) column. The rows consisted of the 6 substances sweet potato 1, sweet potato 2, sweet potato 3, carrot 1, carrot 2, and carrot 3. Times were recorded to the hundredths place and recorded in the table into their respective locations. Once all 18 surface to surface times were recorded, the mean was taken of T1, T2, and T3 of each of the six substances. The mean was recorded in a column to the right of the T3 column. To the right of the mean column, rate (1/mean) was recorded for each of the six substances. Although it remained constant throughout the experiment, concentration was listed as 50%. The table could then be used to make a graph comparing substances and rate of surface to surface time that would elude to enzyme
The Effect of pH on Enzyme Activity. pH is a measure of the concentration of hydrogen ions in a solution. The higher the hydrogen ion concentration, the lower the pH. Most enzymes function efficiently over a narrow pH range. A change in pH above or below this range reduces the rate of enzyme reaction. considerably.
Dependent Variables Amount of vitamin C in fruit juices. Controlled Variable Same amount of liquid for each fruit juice.... ... middle of paper ... ...
Without enzymes, reactions wouldn’t occur and living organisms would die. For instance, the enzyme in the stomach breaks down large molecules to smaller molecules to absorb nutrition faster. Researchers experimented with enzyme activity with a potato extract. Researchers will test enzyme activity by increasing and decreasing pH levels, lowering and increasing temperature, and substrate concentration effects. In the first experiment, researchers hypothesized whether different pH levels would change how much Benzoquinone are created and how will the enzymes function in neutral pH levels than higher and lower levels. Researchers used potato extract and different levels of pH to test their hypothesis. In addition, researchers questioned at what temperature does the greatest amount of potato extract enzyme activity take place in. Researchers then hypothesized that the results would indicate the greatest amount of potato enzyme activity level will take place in room temperature. In this experiment, researchers used potato extract and different temperature levels to test the hypothesis. Moreover, researchers wanted to test the color intensity scale and how specific catechol oxidase is for catechol. In this experiment, researchers used dH2O, catechol solution, hydroquinone, and potato extract. Lastly, researchers tested the substrate concentration and how it has an effect on enzyme activity. In this experiment researchers used different measurements of catechol and 1cm of potato extract. Researchers hypothesized that the increase o substrate would level out the enzyme activity
Independent variables: The temperature of hcl gas will be decreased and increased throughout the experiment.