Question 1

Which of the following statements about enzyme kinetics is correct?

Accepted Answer

K_m can have units of $$mM$$

Question 2

An uncompetitive inhibitor binds to:

Accepted Answer

ONLY ES, the enzyme-substrate complex

Question 3

In Step Z of the chymotrypsin mechanism, the His-57 side chain is acting as a ____________ to activate a molecule of water for _______ attack on the carbonyl carbon ________ of the acyl-enzyme intermediate.

Accepted Answer

general base catalyst / nucleophilic / electrophile

Question 4

In Step X of the chymotrypsin mechanism, the oxyanion pocket is stabilizing the high-energy ________ to _______ the activation free energy barrier.

Accepted Answer

transition state / decrease

Question 5

Which of the following statements about the Michaelis-Menten and Lineweaver-Burk plots for EnzA is correct?

Accepted Answer

The K_m of EnzA in the absence of inhibitor is 20 mM

Question 6

In the presence of 0.1 mM inhibitor, the apparent $$V_{max}/K_m$$ for EnzA is ______ the $$V_{max}/K_m of $$EnzA without inhibitor.

Accepted Answer

Less than

Question 7

Which statement accurately describes the structure of monosaccharide X?

Accepted Answer

The hexofuranose is a D-sugar

Question 8

Which of the following statements accurately describes the stereochemistry of the three monosaccharides X, Y, and Z?

Accepted Answer

Monosaccharide Y is a diastereomer of monosaccharide Z

Question 9

Residue X1 in Polysaccharide X is a(n):

Accepted Answer

Alpha-D-glucopyranose residue

Question 10

The type of glycosidic linkage found in Polysaccharide Y can be described as:

Accepted Answer

Beta-(1,4)

Question 11

The glycosidic linkage found in Polysaccharide X is also found in _____, creating _____.

Accepted Answer

Cellulose / tightly packed sheet-like structures with many interchain H-bonds & van der Waals interactions

Question 12

Which of the following base pairs (from the provided image) involves the formation of hydrogen bonds between two PURINE bases?

Accepted Answer

Panel E

Question 13

The Watson-Crick base pair formed in panel F is found in:

Accepted Answer

RNA only

Question 14

Which of the following sequences would form a standard Watson-Crick DNA double helix with the nucleotide sequence 5'-AGCTCGT-3'?

Accepted Answer

5'-TCGAGCA-3'

Question 15

A nucleotide residue contains which of the following components?

Accepted Answer

All of the above

Question 16

As drawn above, the anomeric carbon in the monosaccharide residue at the NON-REDUCING end of the disaccharide maltose is in the ______ configuration. The anomeric carbon in the monosaccharide residue at the REDUCING end of the disaccharide maltose is in the ______ configuration.

Accepted Answer

Alpha / Beta

Question 17

The process of mutarotation CAN spontaneously change the configuration of the anomeric carbon in the residue at the _________ end of maltose, but it CANNOT change the configuration of the anomeric carbon in the residue at the _________ end of maltose.

Accepted Answer

Reducing / non-reducing

Question 18

In the repeating disaccharide unit of keratan sulfate, which carbon in Residue 1 is the anomeric carbon?

Accepted Answer

C-1

Question 19

Which of the following best explains why the glycosidic linkage in cellulose results in a rigid, sheet-like structure?

Accepted Answer

The beta-(1,4) linkage allows for extensive interchain hydrogen bonding and van der Waals interactions

Comprehensive Study Guidance for BIOC-2010/2015: Organic Chemistry of Biomolecules

Guida di studio - Domande di pratica

Study guide - Flashcard