EXPERIEMNT 4

ENZYMES

are compounds, usually globular proteins, act as biological catalysts for biochemical reactions.

TRUE

TRUE OR FALSE

Without enzymes, life WOULD NOT be possible since biochemical reactions would not occur as fast as they would.

1. Oxidoreductases

2. isomerases

3. transferases

4. ligase

5. lyase

what are the types of enzymes?

1. size

2. specificity

3. reactivity

4. reactivity to substances called substrates

Compared to typical laboratory catalysts, enzymes differ in terms of?

TRUE

TRUE OR FALSE

The type of enzymes present within a cell will dictate the type of reactions that occur within the cell

1. pH

2. Temperature

3. enzyme concentration

4. substrate concentration

The activity of enzymes is affected by several factors

TRUE

TRUE OR FALSE

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 biochemical reactions.

1. Study the effect of enzyme concentration and pH on the enzyme’s activity

2. Determine the enzyme’s optimum pH.

WHAT ARE THE OBJECTIVE OF EXPERIEMNT 4 (day 1)

• 0.2 M Phosphate buffer (pH 6.9)

• 1% starch solution

• Iodine solution (technical grade)

• pH buffer: 2, 4, 7, 10

WHAT ARE THE 4 REAGENTS IN EXPERIMENT 4 (day 1)

Temperature-controlled water bath

Temperature-controlled water bath

WHAT IS THE EQUIPMENT USED IN EXPERIEMNT 4 (day 1)

3

DROPS OF SALIVA

test tube 2 : ___ drops of saliva from tube 5

6

test tube 3 : ___ drops of saliva from tube 5

10

test tube 4 : ___ drops of saliva from tube 5

all ; none

FILL IN THE BLANKS

most ; low (1)

FILL IN THE BLANKS

some ; moderate (2)

FILL IN THE BLANKS

none ; high (3)

FILL IN THE BLANKS

2

Test tube 1 + Test tube pH____

4

Test tube 2 + Test tube pH___

7

Test tube 3 + Test tube pH____

10

Test tube 4 + Test tube pH_____

1. Study the effect of temperature and the presence of inhibitors on the enzyme’s activity; and 2. Determine the enzyme’s optimum temperature.

WHAT ARE THE OBJECTIVE OF EXPERIMENT 4 (day 2)

0.2 M Phosphate buffer (pH 6.9)

1% starch solution

Iodine solution (technical grade)

1% NaCl

95% ethanol

AgNO3

WHAT ARE THE REAGENTS OF EXPERIMENT 4 (day 2)

2

DAY 2:

Collect ___mL of saliva into a beaker

ice bath

EFFECT OF TEMPERATURE

Test tubes 1 and 4 in an__________

37°C

EFFECT OF TEMPERATURE

Test tubes 2 and 5 at__________

100°C

EFFECT OF TEMPERATURE

Test tubes 3 and 6 at ______