#Question id: 631
#Section 2: General Biology
Two curves showing the rate versus substrate concentration are shown below for an enzyme-catalyzed reaction. One curve is for the reaction in the presence of substance X. The other curve is for data in the absence of substance X. Examine the curves and tell which statement below is false.
#Question id: 634
#Section 2: General Biology
An enzyme has a Vmax of 50 micromol product formed (minute x mg protein)-1 and a Km of 10 microM for the substrate. When a reaction mixture contains the enzyme and 5 microM substrate, which of the following percentages of the maximum velocity will be closest to the initial reaction rate?
#Question id: 635
#Section 2: General Biology
The enymatic rate constant (kcat/Km) of orotidine 5ʹ-phosphate decarboxylase is 6 x 107 M-1s-1 and the nonenzymatic rate constant (kn) is 3 x 10-16 s-1. What is the value of the enzymeʹs catalytic proficiency?
#Question id: 636
#Section 2: General Biology
DNA polymerase contains a lysine residue that is important for binding to DNA. Mutations were found that converted this lysine to either glutamate, glycine, valine, or arginine. Which mutations would be predicted to be the most and least harmful to the ability of the enzyme to bind DNA?
|
Most |
Least |
|
|
(A) |
Valine |
Aspartate |
|
(B) |
Glycine |
Arginine |
|
(C) |
Arginine |
Glycine |
|
(D) |
Glutamate |
Arginine |
#Question id: 638
#Section 2: General Biology
Match the following class of enzymes with them
|
Enzyme |
Class of enzyme |
|
A. Hexokinase |
1 |
|
B. Phosphoglucoisomerase |
2 |
|
C. Glyceraldehyde 3-phosphate dehydrogenase |
3 |
|
D. Phosphoglycerate mutase |
4 |
|
E. Enolase |
5 |
|
F. Aldolase |
#Question id: 639
#Section 2: General Biology
Match the coenzymes in column I enzymes to class of enzymes in column II
|
A. Phosphofructokinase |
1. Redox reaction |
|
B. Enolase |
2. Phosphoryl shift |
|
C. Phosphoglycerate mutase |
3. Dehydration |
|
D. Glyceraldehyde 3 Phosphate dehydrogenase |
4. Phosphoryl transfer |