Enzyme Kinetics and Factors that affects enzymatic reactions

Question 1

Enzymes catalyze physiologic reactions by __ the activation energy level that the reactants must reach

Answer 1

Lowering

Question 2

The greater the activation energy level required, the __ the reaction to proceed

Answer 2

Longer

Question 3

The lower the activation energy, the __ formation of products

Answer 3

Faster

Question 4

Enzymes combined with only one substrate and catalyze only one corresponding reaction

Answer 4

Absolute specificity

Question 5

Enzymes combined with all substrate containing all chemical group

Answer 5

Group Specificity

Question 6

Enzyme that will combine with a specific
chemical bond present

Answer 6

Bond specificity

Question 7

Enzymes combined with only one optical isomer

Answer 7

Stereoisomeric specificity

Question 8

The greater the substrate present, the more/higher enzymatic reactions/higher rate of enzyme activity can occur

Answer 8

Substrate concentration

Question 9

When the substrate concentration reached a maximal value, enzymes are exhausted already, addition of substrate could no longer result in increased rate of reaction. This is called

Answer 9

Saturation kinetics

Question 10

Reaction rate is proportional to the substrate concentration (increasing) thus, (greater substrate, more enzymatic reaction) but no reaction in maximal value

Answer 10

First order Kinetics

Question 11

Only a fixed number of substrate concentration (in excess) is converted to product per second. This is usually used in the laboratory.

Answer 11

Zero order Kinetics

Question 12

The higher the enzyme concentration, the faster is the reaction because the more enzymes present, the greater is the binding site with a substrate which is converted into a product.

Answer 12

Enzyme concentration

Question 13

Most physiologic reactions occur in what pH?

Answer 13

7.0 to 8.0 (near to plasma pH)

Question 14

What will happen if the pH is too acidic or basic?

Answer 14

It will denature the protein of enzyme

Question 15

Exemption to this because they can react in extremely high or low pH

Answer 15

Phosphatases

Question 16

can react to pH 3.0- 5.0

Answer 16

Acid phosphatase

Question 17

can react to pH 9.0

Answer 17

Alkaline phosphatase

Question 18

Has a vital role in enzyme reaction.

Answer 18

Temperature

Question 19

Assay temperature should be constant within

Answer 19

+/- 0.1 degC

Question 20

Incubation period is slow

Answer 20

Room temp (25-30degC)

Question 21

Incubation period is faster

Answer 21

Warm or faster temp (37degC)

Question 22

Optimum temperature for enzymatic activity

Answer 22

37degC

Question 23

Start of significant decrease in enzyme activity (start of protein denaturation of their tertiary structure)

Answer 23

40-50degC

Question 24

Most enzymes are denatured *significant denaturation

Answer 24

56degC

Question 25

Enzyme is inactivated

Answer 25

60-65degC

Question 26

For every 10degC increase in temp, there will be a two-fold increase in enzyme activity.

Answer 26

Temperature Quotient (Q10)

Question 27

Most enzymes are thermolabile except to placental alkaphos specifically

Answer 27

Regan Alkaphos (Thermostable)

Question 28

Agents that could interfere with enzyme-substrate reaction, they could prevent substrate conversion

Answer 28

Inhibitors

Question 29

Competes with the substrate to the active site of the enzyme (can physically bind to the active site of enzyme).

Answer 29

Competitive inhibitor

Question 30

This inhibitor can affect the velocity of enzyme reaction

Answer 30

Competitive inhibitor

Question 31

T/F: . As you add more competitive inhibitors, it will decrease or slow down the activity.

Answer 31

TRUE

Question 32

Does not compete with the substrate to the active site of enzyme

Answer 32

Noncompetitive inhibitor

Question 33

Noncompetitive inhibitor bind to other site of enzyme which is the

Answer 33

Allosteric site

Question 34

Bind with the enzyme- substrate complex

Answer 34

Uncompetitive Inhibitor

Question 35

General temperature for enzyme for storage

Answer 35

Freezer temp (-20degC or colder)

Question 36

If multiple freeze-thawing is done, what will happen?

Answer 36

It could damage and destroy enzymes in the serum.

Question 37

The ideal temp for storage of substrate and coenzyme (reagents)

Answer 37

Ref temp (2-8degC)

Question 38

The ideal temp for storage of serum (Target: LDH)

Answer 38

Room temp (20-24 degC)

Question 39

Hemolysis can falsely __ the serum-enzyme concentration

Answer 39

Elevate