Enzymes and Zwitterions

Which one of the following statements about Enzymes is incorrect

• Enzymes are not consumed in the reaction

• Enzymes change shape to accommodate the substrate

• Enzymes are catalysts

• Enzymes are still active after being cooled

• Enzymes are still active after being heated

Which one of the following statements about Enzymes is incorrect

• Enzymes lower the activation energy of a reaction

• Enzymes increase the number of collisions between the reactants

• Enzymes aid bond breaking of the reactants

• Enzyme increase the proportion of successful collisions between the reactants

• Enzymes are not consumed in the reaction

Which one of the following is not a similarity between the induced fit and lock and key model of enzymes:

• Both require the substrate to enter the active site

• Both require the substrate to form intermolecular bonds with the functional groups in the active site

• Both require the tertiary structure of the enzyme to remain fixed

• Both leave the enzyme intact after the reaction

• Both models do not apply to denatured enzymes

The substrate refers to

• The enzyme

• The reactants

• The products

• The complex

• The tertiary and quaternary structures

Alanine (shown here) is chiral. All naturally occurring amino acids are in the L-configuration (none in the D-configuration)

The enzyme that catalyses the condensation of alanine and glycine into a dipeptide:

• Will only accept the L-isomer of alanine

• Will accept any isomer of alanine

• Will accept any amino acid provided that it is L

• Will accept both L and D amino acids

• It is still unknown what this enzyme will accept

What is not involved in denaturation of a protein?

• Exposure to conditions outside it's optimal range

• Disruption of the tertiary structure

• Disruption of the quaternary structure

• Disruption of the secondary structure

• Disruption of the primary structure

When a protein denatures

• It can be reassembled via condensation reactions

• It can be reassembled via hydrolysis reactions

• It can be reassembled via amidation reactions

• It can be reassembled via enzyme catalysis

• It cannot be reassembled

The effects of low temperature on enzymes are:

• Reduced function due to disruption of the secondary, tertiary and quaternary structures

• Reduced function due to disruption of the primary structure

• Reduced function due to insufficient flexibility in the enzyme structure

• Increased function due to approaching of optimal conditions

• Increased function due to increasing the proportion of successful collisions

The effects of high temperature on enzymes are:

• Reduced function due to disruption of the secondary, tertiary and quaternary structures

• Reduced function due to disruption of the primary structure

• Reduced function due to insufficient flexibility in the enzyme structure

• Increased function due to approaching of optimal conditions

• Increased function due to increasing the proportion of successful collisions

Which of the following is possible while still maintaining enzyme activity:

• Cooling the enzyme, then returning it to its optimal temperature

• Heating the enzyme, then returning it to its optimal temperature

• The enzyme cannot be taken outside its temperature range with out permanently deactivating it (denaturing)

• The enzyme will still be active after both heating or cooling