BIOLOGY 103 FALL, 2002 LAB 5

All measurements were taken at 15 second intervals.

First experiment: 0, .2, .4, .4, .6, 1, 1.2, 1.4, 1.6, 1.8, 2, 2, 2.2, 2.2, 2.4, 2.6, 2.6, 2.8, 2.8, 3, 3, 3.

After change in H2O2 level (Experiment #2): .4, .4, .5, .6, .7, .8, 1, 1.1, 1.3, 1.4, 1.5, 1.6, 1.7, 1.7, 1.8, 1.9, 2, 2, 2, 2.2, 2.2, 2.3, 2.4

We used less H2O2 in the second experiment which raised the rate of reaction, resulting in a lower production of oxygen within the same time period.

Reaction Rate (First experiment)= .4
Reaction rate (second experiment)= .7

reaction rate = (1.2-.9)/3 = .1/1 minute

method: our portion of the experiment was to see if changing temperature would affect reaction time of the enzyme. We hypothesized that temperature woudl slow down the reaction time by making the oxygen release per minute lower than the test run that we first ran.
we found that the reaction time during trial one of the experiment was much higher (.8/1minute) than that of our reaction time for experiment number five.
mande adn debe

Experiment 1, Trial 1 (Volume of Oxygen in CCs, taken at 15 second intervals):
0,0,0,.2,.4,.5,.62,1,1.1,1.2,1.4,1.5,1.6,1.8,2,2.2,2.3,2.4,2.6,2.6,2.7,2.8,2.9,3,3.1,3.2,3.3,3.4,3.5,3.6,3.6,3.7,3.7,3.8,3.9,3.9,3.95,3.95,4,4.1,4.2,4.2,4.2,4.2
Reaction Rate:.533

Experiment 2, Trial 1:
.4,.4,.5,.6,.8,1,1.2,1.4,1.8,2,2.2,2.4,2.6,2.9,3,3.2,3.3,3.6,3.7,3.9,4,4.1,4.4,4.5,4.6,4.7,4.8,4.9,4.9,5,5.1,5.18,5.2,5.2,5.3,5.35,5.4,5.5,5.5,5.6,5.7,5.8,5.8,5.8,5.8
Reaction Rate:.83

Experiment 2, Trial 2:
0,.1,.2,.5,.7,1,1.2,1.4,1.6,1.8,2.2,2.2,2.4,2.6,2.7,2.9,3.2,3.2,3.4,3.7,3.9,4.1,4.2,4.3,4.4,4.6,4.6,4.8,4.8,4.9,5,5,5.1,5.2,5.2,5.2,5.3,5.4,5.4,5.4
Reaction Rate: .76

When we increased the amount of H2O2, the reaction became quicker and more noticeable to the naked eye.
We conclude that as the ratio between the two components decreases, the reaction becomes more rapid and stronger.

(All volume units are in cc.)

EXPERIMENT #1:Standard Catalase at Room Temp.

DATA: .1,.2,.3,.4,.6,1.0,1.2,1.5,1.5,1.8,2.0,2.3,2.4,2.5,2.7,2.8,
2.9,3.0,3.2,3.3,3.5,3.6,3.7,3.7,3.7

REACTION RATE: Volume at 2 minutes = 1.5cc
Volume at 4 minutes = 2.8cc
(2.8cc - 1.5cc)/2 = 0.65cc/min

EXPERIMENT #4:Change of pH of Buffer
(Due to time constraints we were only able to conduct one trial.)

DATA: 0.0,0.0,0.0,0.0,0.1,0.2,0.2,0.2,0.3,0.3,0.4,0.5,0.6,0.6,0.7,0.8,
0.8,0.9,1.0,1.1,1.2,1.2,1.3,1.4,1.4,1.5,1.6,1.7

REACTION RATE: Volume at 2 minutes = 0.2cc
Volume at 4 minutes = 0.8cc
(0.8cc - 0.2cc)/2 = 0.3cc/min

CONCLUSION: The pH effects the reaction rate. Lowering the pH
significantly slowed the rate of the reaction between the
enzyme and the hydrogen peroxide.

Obviously the enzyme reacts with the hydrogen peroxide to release the oxygen. The pH only effects the reaction time. It does not effect the amount of oxygen that is produced by the chemical reaction. As you can see from our second experiment in which we changed the pH of the buffer, the reaction would still produce the same amount of oxygen that the first experiment did but at a much slower pace.

This is our data:
Experiment 1:
0, .2, .4, .6, .8, 1.0, 1.2, 1.4, 1.5, 1.6, 1.65, 1.8, 1.9, 2.0, 2.0, 2.05, 2.1, 2.15, 2.2, 2.2, 2.3, 2.35, 2.4, 2.4, 2.4, 2.4
Total time: 6 minutes 30 seconds
Rate: .2 ml/min

Experiment 2C:
Trial 1:
.2, .35, .6, .85, 1.2, 1.5, 1.8, 2.0, 2.3, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.7, 3.8, 4.0, 4.1, 4.2, 4.25, 4.4, 4.5, 4.6, 4.6, 4.6, 4.65, 4.7, 4.8, 4.8, 4.8, 4.8
Total time: 8 minutes
Rate: .6 ml/min

Trail 2:
.1, .2, .4, .6, .8, 1.1, 1.4, 1.7, 2.0, 2.2, 2.4, 2.7, 3.0, 3.1, 3.3, 3.4, 3.6, 3.8, 4.0, 4.1, 4.3, 4.4, 4.5, 4.6, 4.65, 4.8, 4.8, 5.0, 5.0, 5.1, 5.2, 5.2, 5.4, 5.4, 5.4, 5.4
Total time: 9 minutes
Rate: .7 ml/min

Trial 3:
.1, .2, .4, .6, .8, 1.1, 1.4, 1.7, 2.0, 2.2, 2.4, 2.6, 2.7, 3.0, 3.1, 3.2, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.0, 4.2, 4.2, 4.3, 4.4, 4.4, 4.4, 4.5, 4.6, 4.6, 4.6, 4.7, 4.8, 4.8, 4.8, 4.8
Total time: 10 minutes
Rate: .52 ml/min

Christine Traversi
Heather Price

Trial B Results
.6
.8
.8
1.0
1.2
1.3
1.5
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.3
3.4
3.5
3.6
3.8
3.9
4.0
4.1
4.2
Trial B reaction rate: .075
(Trial A reaction rate: .015)

Methods: Every fifteen seconds recorded reaction measurement from the injection of the H2O2.

Observations: We found a variety of observations. In trial A, nothing really moved and when it did, it was slow. In Trial B, the results were similiar to the original.

Our enzyme did not change because our rate stayed the same as X went up.

0,0,0,0,0,.1,.2,.2,.4,.4,.4,1.1,1.3,1.5,1.5,1.8,2.0,2.2,2.2,2.3,2.4,2.6,2.8,2.8,2.8

Reaction Rate: 0.7 O2/minute

Trial 2
(Increased Temp)

0,.1,.4,.6,1.0,1.3,1.6,1.8,2.2,2.4,2.8,3.0,-,-,-,3.8,3.8,4.0,4.1,4.2,4.2,4.3,4.3,4.3

Reaction Rate: .8 O2/minute

Trial 3
(Increased Temp)

0,0,.2,.6,.8,1.0,1.4,1.6,1.8,2.2,2.4,2.8,3.2,3.2,3.2,3.2,3.5,3.8,4.0,4.0,4.1,4.1,4.2,4.2,4.3,4.3,4.3

Reaction Rate: .8 O2/minute

Our data shows that the reaction rate was slightly faster when the chemicals at higher temperatures. The amount of overall O2 volume was higher at the larger temp, however we only did one trial at room temperature, toconfirm this change we would need to do another trial at room temp. Our story is that the hightened temperature allowed for a faster reaction rate because the molecules were moving around faster. that's our story and we're sticking to it....for a while anyway.....

Rate of Oxygen produced:
Ex 1 (control):0.6 cc/min
Ex 2 (pH 2.0): 0.067 cc/min

Observations:
-Reaction rate significantly decreased.
-x(plateu value) significantly decreased.
Story- The pH level affects how the Catalase works.

Trial 1:
.2, .4, .8, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.0, 3.2, 3.3, 3.4, 3.4, 3.5, 3.6, 3.6, 3.7, 3.8, 3.8, 4.0, 4.0, 4.0
The rate of change is fairly constant for 4 minutes at an additional .2 cm for every 15 seconds. After 4 minutes it changes .2 cm for every 30 seconds until it stabilizes after 6 min 40 sec reaching 4.0 cm of oxygen in the tube.

Introduction:
This experiment demonstrates the effects of the enzyme Catalase on hydrogen peroxide.

Methods:
We were given a nicely set-up apparatus consisting of a ring stand and a Scholander respirometer. We had two vials one of which was a control vial and the other was the experimental vial. In the control vial we put in 0.5cc of H2O2 and 4.5cc of pH 7.4 buffer and in the experimental vial we first put in 1.5cc of Catalase and 3cc of the buffer. The two vials were attached to the respirometer and then 0.5cc of H2O2 was injected into the experimental vial and the small plug was pushed in and at the same time the oxygen syringe was slowly pulled up and different volumes of oxygen were measured for different time intervals. The methods are the same for both trial 1 and trial 2.

Observations:
Trial 1
Time/sec Volume O2
15 .2
30 1
45 1.6
60 2.2
75 2.7
90 3
105 3.1
120 3.2
135 3.2
150 3.4
165 3.4
180 3.6
195 3.8
210 3.8
225 3.9
240 3.9
255 3.9
270 3.9
. .
. .
. .
. .

Trial 2(performed twice)
Time/sec Volume O2
15 .2/.4
30 .9/.8
45 1.4/1.4
60 1.8/1.8
75 2.2/2.0
90 2.4/2.4
105 2.7/2.7
120 2.8/2.8
135 3.0/3.0
150 3.2/3.2
165 3.2/3.3
180 3.4/3.4
195 3.6/3.5
210 3.8/3.6
225 3.9/3.8
240 3.9/3.9
255 3.9/3.9
270 3.9/3.9
. .
. .
. .
. .

Conclusion/ThE StoRY:
Rate of Concentration= 1.6/2= 0.8cc of O2/min
Our experiment remained the same, thus observations remained similar and hence we conclude with our rate of concentration and alas, no remarks on enzyme behavior!!!

Our results from experiment two were:
DATA: .1, .5, 1, 1.5, 1.9, 2, 2.2, 2.4, 2.4, 2.6, 2.6, 2.6
Our data was collected over a period of three minutes. This experiment was the first trial of adding .40 H2O2 to the experimental mixture, which contained 1.50 ml of Catalase and 3.10 ml of 7.4 Buffer for a total volume of 5.00 ml.

Our results from the second trial of the same experiment were:
DATA: .1, .5, 1, 1.4, 1.8, 2.1, 2.2, 2.4, 2.6, 2.6, 2.8, 2.8

In the first experiment the rate we computed over two minutes was 1 O2/minute. In the second experiment the rate we computed over two minutes was .9 O2/min. When we add less H2O2, we ended up with less O2 per minute, but our rate was the same in both experiments. This means that the rate is independent of the amount of H2O2 that is added. Our conclusion is that the rate is determined by the enzyme that is added. Since the amount of enzyme was the same in both experiments, the rate should stay the same. Since it did, our conclusion has been proven.

1.8, 2.1, 2.4, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.25, 3.3, 3.3, 3.35, 3.4, 3.45, 3.5, 3.55, 3.6, 3.6, 3.6

Experiment 4B:
(Experiment 4 was using a buffer of 4.01 pH instead of the previously used pH level of 7.4)
Trial 1: .2 cc after 15 seconds
Trial 2: .2 cc after 15 seconds.

In both of our trials for experiment 4, the brody shot up quickly, equalling .2 cc, but then stopped moving completely.

This made us come to the conclusion that the higher the buffer's pH is, the longer the reaction will run, and the lower the buffer's pH is, the shorter the time of the reaction. This may mean that the lower the buffer's pH, the less effective the catalase (the enzyme) is at breaking apart the peroxide.

Our rate = .2/15= .01333 cc/sec. However, this rate could be deceiving because while we took the first measurement at fifteen seconds, the oxygen had stopped moving before that.

Trial A: (at room temperature)
.2, .4, .8, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.0, 3.2, 3.3, 3.4, 3.4, 3.5, 3.6, 3.6, 3.7, 3.8, 3.8, 4.0, 4.0, 4.0
The rate of change was fairly constant for 4 minutes at an additional .2 cm for every 15 seconds. After 4 minutes it changed .2 cm for every 30 seconds until it stabilized after 6 min 40 sec reaching 4.0 cm of oxygen in the tube.

Our rate between 1 and 3 minutes was 0.80 O2 per minute.

Trial B: (at heated temperature)
test #1
.3, .8, 1.3, 2.0, 2.4, 2.7, 3.0, 3.2, 3.4, 3.6, 3.7, 3.8, 4.0, 4.1, 4.2, 4.2, 4.3, 4.4, 4.4, 4.5, 4.6, 4.6, 4.6, 4.7, 4.8, 4.8, 4.8, 4.9.

Our rate between 1 and 3 minutes was 0.90 O2 per minute.

test#2
.2, .8, 1.4, 2.0, 2.5, 2.8, 3.2, 3.4, 3.6, 3.8, 4.0, 4.1, 4.2, 4.4, 4.4 4.6, 4.6, 4.7, 4.8, 4.8, 4.9, 5.0, 5.0, 5.0

Our rate between 1 and 3 minutes was 1.05 O2 per minute.

** Our average rate of O2 per minute for Trial B was 0.98***

Discussion:
With higher temperature the rate of the O2 per minute was greater than the rate of the room temperature by a difference in rate of 0.18 O2 per minute.

The control trial involved 1.5cc of the Catalase, 0.50cc of the Hydrogen Peroxide, and 3.00cc of the buffer. The readings were taken every 15 seconds.

Our control set of data was as follows:

.4, .8, 1.2, 1.6, 2, 2.2, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, ~3.2, 3.2, 3.2,

3.3, 3.3, 3.4, 3.4, 3.4

Our next trials involved 0.6cc of Hydrogen Peroxide, 2.9cc of the buffer, and the enzyme remained constant at 1.5cc. The rate from our first trial (for minutes 1-3) was 0.7cc/minute of oxygen; the rate from the data set below with the increased amount of Hydrogen Peroxide is 1cc/ minute. Our data for the second set was as follows:

.3, 1.0, 1.8, 2.4, 2.8, 3.2, 3.5, 3.7, 3.9, 4.1, 4.2, 4.4, 4.4, 4.5, 4.6,

4.7, 4.8, 4.8, 4.9, 5.0, 5.0, 5.1, 5.2, 5.2, 5.2

Based on our scientific observations, we have concluded that increasing the amount of HP added to the enzyme increases the rate at which oxygen converts to a gas. NOTE: Although the time is different on each of these trials, we feel that it is not really legitimate to say that the amount of HP affects time as well because our first trial was shorter than the control.

Summary of Data from Trial 2 (with same substances, but chilled):
Volume of Oxygen: .2, .2, .6, .8, 1, 1.2, 1.6, 1.8, 2, 2, 2.2, 2.4, 2.4, 2.6, 2.6, 2.8, 2.8, 3.0, 3.0, 3.0, 3.2, 3.2, 3.2, 3.3, 3.3, 3.4, 3.4, 3.4, 3.5, 3.6, 3.6, 3.6, 3.7, 3.7, 3.8, 3.8, 3.8, 3.8, 3.8,3.8, 3.8
Rate of Reaction: .3 mL of Oxygen/minute

Summary of Data from Trial 3 (with same substances, but chilled):
Volume of Oxygen:.2, .4,.8, 1. 1.4, 1.7, 2, 2.2, 2.4, 2.6, 2.8, 3.0, 3.0, 3.2, 3.4, 3.6, 3.6, 3.7, 3.8, 3.8, 3.9, 4.0, 4.0, 4.0, 4.1, 4.1, 4.1, 4.1, 4.2, 4.2, 4.2, 4.2
Rate of Reaction: .3 mL of Oxygen/minute

Cooler temperatures mean slower molecules. Thus, when all the solutions were chilled, their slower molecular movement accounts for the drop in reaction rate. Rock on.

Experiment #1:
All measurements were taken at 15 second intervals.
.8, 1, 1.2, 1.6, 2, 2.4, 2.5, 2.7, 2.8, 2.9, 3, 3, 3.1, 3.2, 3.2, 3.2
The solution reacted for 4 full minutes (240 seconds).

Experiment #4c:
3.00cc of pH 10.4 buffer was added to the original experiment.
All measurments were taken at 15 second intervals.
.6/.6, .8/.8, 1/1.2, 1.3/1.4, 1.6/1.7, 2/2, 2.2/2.3, 2.4/2.6, 2.7/2.8, 2.9/3, 3.1/3.2, 3.2/3.4, 3.4/3.5, 3.5/3.6, 3.6/3.8, 3.7/3.9, 3.8/4, 3.8/4.1, 3.9/4.2, 4/4.3, 4/4.4, 4.1/4.4, 4.2/4.4, 4.2, 4.2
The solution reacted for 375sec/345sec.

When a higher pH was added to the experiment, the solution reacted for a longer time. The rate of reaction was also higher. In the original solution, the rate of reaction was .4 O2/min. The average rate for the experiment with the added pH was .692 O2/min. The higher pH level is condusive to the reaction; it helps remove more oxygen for a longer amount of time.

Volume Gas reading every 15 seconds (ml)
Experiment 1: 0.2, 0.4, 0.8, 1.4, 1.6, 2.0, 2.2, 2.5, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.2, 3.3, 3.4, 3.4, 3.4, 3.5, 3.6, 3.6, 3.6, 3.6
rate volume O2/min (0-2mins): 1.3
rate volume O2/min (1-3mins): 0.8
rate volume O2/min (1-4mins): 0.633

Experiment 3 increase in amount of calalase
3a: 0.6,1.4,2.0,2.4,2.8,3.1,3.2,3.4,3.5,3.6,3.7,3.8,3.8,3.8,3.9,4.0,4.0,4.1,4.2,4.2,4.2,4.2

rate volume O2/min (0-2mins): 1.7

3b:
0.4, 0.8, 1.4, 2.0, 2.4, 2.7, 2.8, 3.0, 3.0, 3.1, 3.2, 3.2, 3.4, 3.4, 3.5, 3.6, 3.6, 3.6, 3.6

rate volume O2/min (0-2mins): 1.5
rate volume O2/min (1-3mins): 0.7

3c:
0.8, 1.6, 2.2, 2.6, 3.0, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.8, 3.9, 4.0, 4.1, 4.1, 4.1, 4.2, 4.2, 4.2

rate volume O2/min (0-2mins): 1.7

An increase in the amount of calalase yielded an increase in the rate of production of O2 gas. It did not yield more O2 gas.

Trial 2 (less enzyme):
.2, .3, .4, .6, .8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.5, 2.6, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.5, 3.6, 3.7, 3.7, 3.8, 3.9, 3.9, 4.0, 4.0, 4.0
total time: 8 minutes 15 seconds
Rate from minute 2 to minute 5: .6 O2/minute

Trial 3 (less enzyme):
.1, .2, .3, .4, .6, .75, .9, 1.1, 1.3, 1.5, 1.8, 1.9, 2.1, 2.2, 2.4, 2.6, 2.8, 2.9, 3.0, 3.1, 3.2, 3.4, 3.5, 3.6, 3.7, 3.8, 3.8, 3.9, 4.0, 4.1, 4.2, 4.2, 4.3, 4.3, 4.3
total time: 8 minutes 45 seconds
Rate from minute 2 to minute 5: .66 O2/minute

Trial 4 (less enzyme):
.0, .1, .2, .4, .5, .6, .8, 1.0, 1.1, 1.3, 1.4, 1.6, 1.8, 1.9, 2.0, 2.2, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.05, 3.1, 3.3, 3.4, 3.45, 3.6, 3.6, 3., 3.8, 3.9, 4.0, 4.0, 4.0
total time: 9 minutes
Rate from minute 2 to minute 6: .56 O2/minute

Change in catalase concentration--Experimanet #3 Trial A

For trial 1, the control, our volume of oxygem as measured every 15 seconds is as follows 0,0,0,0,.20.4,.6,.9,1.2,1.5,1.8,2.0,2.2,2.4,2.6,2.8,3.0,3.1,3.2,3.4,3.5,3.6,3.75,3.9,4.0,4.1,4.2,4.25,4.4,4.4,4.45,4.5,4.5,4.5
The reaction rate from 2 minutes to 6 minutes is 0.75 oxygen per minute.

In trial 2, we used 0.5 cc of the catalase in the experimental. Our volume of oxygen as measured every 15 seconds is as follows
0,0,0.5,0.08,0.09,0.1,0.11,0.12,0.15,.20,.22,.25,.28,.31,.34,.?,.8,.9,1.0,1.01,1.1,1.2,1.21,1.3,1.38,1.4,1.5,1.55,1.6,1.62,1.65,1.8,1.85,1.9,1.9,2.0,2.0,2.1,2.1,2.2,2.2,2.21,2.3,2.35,2.35,2.4,.2.4,2.4
The reaction rate from 2 minutes to 6 is 0.295 oxygen per minute.

In trial 3, using the same amount of catalase as trial 2, our volume of oxygen as measured every 15 seconds is as follows
0,0,.1,.1,.1,.1,.15,.2,.23,.25,.3,.4,.5,.5,.6,.65,.7,.8,.82,.9,.95,1.0,1.05,1.1,1.2,1.23,1.3,1.4,1.42,1.5,1.55,1.6,1.63,1.7,1.75,1.8,1.82,1.9,1.95,1.98,2.0,2.05,2.1,2.15,2.2,2.22,2.25,2.3,2.3,2.4,2.41,2.42,2.45,2.47,2.5,2.55,2.6,2.6,2.62,2.64,2.67,2.69,2.72.75,2.8,2.81,2.82,2.85,2.88,2.9,2.9,2.91,2.93,2.95,2.97,2.99,3.01,3.03,3.03,3.04,3.05,3.07,3.12,3.15
The reaction rate from 2 minutes to 6 is 0.225 oxygen per minute.

As you can tell, the last two trials took a longer amount of time to plateau. Since the only difference between trials 2 and 3 from trial 1 is the amount of catalase, we can conclude that this is the factor in determining the speed of a chemical reaction. We then gathered that the less amount of catalase, the slower the reaction rate.


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