[LAB 3] Experiment 3 Factor Affecting Enzyme Activity

Question 1

compounds, usually globular proteins, acts as biological catalysts for chemical reactions.

Answer 1

Enzymes

Question 2

Types of Enzymes:

Answer 2

Oxidoreductases
Transferases
Isomareses
Ligases
Lysases

Question 3

Compared to typical laboratoy catalysts, enzymes differ in terms of size, specificity and reactivity to callled substances called

Answer 3

Substrates

Question 4

The type of enzymes present within a ________________ will dictate the type of reaction that occur within the cell.

Answer 4

cell

Question 5

The activity of enzymes is affected by several factors which include temperature, __________________, _______________________ AND __________________.

Answer 5

pH
Enzyme concentration
Substrate Concentration

Question 6

It is important that the optimal conditions are maintained in the cell and in the body in order for enzymes to function properly and increase the rate of _______________.

Answer 6

biochemical reactions

Question 7

Experiment 3 Reagents:

Answer 7

0.2 M Phosphate Buffer (pH 6.9)
1% Starch solution
Iodin Solution
pH buffer: 2,4,7,10

Question 8

Experiment 3 Instrument

Answer 8

Temperature-contolled water bath

Question 9

The students need to borrow the following from the stockroom:

Answer 9

Thermometer
Dropper
Spot Plate
Distilled Water

Question 10

PROCEDURES:

Answer 10

• Saliva Collection
• Effect of Enzyme Concentration
• Effect of pH
• Waste Disposal

Question 11

SALIVA COLLECTION
1. Collect ________ mL of your saliva into a beaker.
2. Measure __________ mL distilled water in graduated cylinder, and add it to the beaker containing the collected saliva. Mix thoroughly and this will be the stock solution

Answer 11

5 mL
20 mL

Question 12

B. EFFECT OF ENZYME CONCENTRATION
1. Label five tubes 1-5.
2. Transfer 2 mL of _______ to test tubes
3. Transfer 3mL of the ______________ from the strock into test tube 5.
4. Place all five tubes in water bath set at ____ C for 5 minutes.
5. Obtain _________ clean dropper and label - one for each solution in the respective test tubes.
6. Remove the test tubes from the ater bath.

Answer 12

1% starch solution
Saliva sample
37 C
5 clean dropper

Question 13

B. EFFECT OF ENZYME CONCENTRATION

TEST TUBE 2
TEST TUBE 3
TEST TUBE 4

Answer 13

3 drops of saliva from the test tube 5
6 drops of saliva from the test tube 5
10 drops of saliva from the test tube 5

Question 14

Add one drop of __________ to each well. Record your observations using the table below as reference.

Answer 14

iodine solution

Question 15

C. EFFECT OF PH
1. Obtain four clean and dry test tubes labeled as: __________, _______, _________, ___________
2. Place 2 mL of the stock saliva sample (prepared from Procedure A) into each of the test tubes. Add 2 mL of the respective buffer solutions.
3. Obtain 4 additional test tubes, labeled as test tubes 1 to 4.
4. Add 2 mL of _____________ to these new tubes.
5. Place all 8 tubes in a water bath set at ____________ for 5 minutes.

Answer 15

pH 2, pH 4, pH 7, pH 10
1% starch solution
37°C

Question 16

Wait for ___________, transfer 3 drops of each reaction mixture (using clean droppers) to a spot plate. Add one drop of the ________to each

Answer 16

15 minutes
iodine reagent

Question 17

excess saliva collected
test tubes with starch
samples in spot plate