The role of Zn2+ in catalysis is usually to: a. Stabilize a (-) charge in the transition state Ob. Act as a nucleophile Act as a base Od. Destabilize a (-) charge in the transition state C.

Which of the following aspects of catalysis by enzymes can NOT be explained by the Fischer Lock and Key Hypothesis? Enzymes will lower the activation energy barrier for reaction. Enzymes will specifically recognize their substrates. Appropriate substrates will bind to the enzyme to form a Michaelis complex. Enzymes have an "active site" where appropriate substrates will be bound. Two of the above cannot be explained by the Fischer "Lock and Key" Hypothesis.

What type of reactions would involve a ligase?   neither anabolic nor catabolic    anabolic    exergonic    catabolic

What is the function of Histidine as part of the catalytic triad? O The alcohol group of histidine makes a nucleophilic attack on a peptide C=O bond. O The imidazole group acts as a general base and extracts a proton from serine activating it to attack the substrate O The imidazole group acts as a general base and extracts a proton from aspartate activating it to attack the substrate O The imidazole group acts as a general base and extracts a proton from aspartate allowing it to activate serine by transferring a proton

Which of the following describe what enzymes such as Chymotrysin accomplish to allow products to form and be released by the enzyme active site? Group of answer choices catalyze chemical eactions that are thermodynamically unfavorable to occur establish a more stable transition state at a higher energy level to perform a catalysis reaction redce the chemical energy held within a chemical bond modify chemical structure of a substrate to "fit" within the active site

Catalysis through proximity and orientation effects involves: (select all that applies) Group of answer choices binding of acidic and/or basic groups in the binding site facilitating chemical reactions by binding substrates close to specific groups binding of substrate in specific, restrictive orientations depending on metal ions for catalysis

Match each reaction description to the type of enzyme that catalyzes the reaction.   1. Oxidation and reduction of compounds 2. Transfers a functional group from one compound to another compound 3. Utilizes water to break bonds within a compound 4. Addition/removal of a group of atoms and bonds within a compound 5. Forms a bond between two compounds   A. Ligase B. Transferase C. Hydrolase D. Oxidoreductase E. Isomerase F. Lyase

An enzyme that catalyzes a reaction such as the one below is alan: || C-0 || C-0 C=0 С —о — Н I| Н-С—Н H- C H H isomerase O kinase O dehydratase O dehydrogenase O phosphorylase O - I

What is X in the following biochemical pathway? RH NH₂+ A. R CH a-ketoglutarate CH3 coenzyme PLP coenzyme TPP aminotransferase decarboxylase D. glutamate R B. NH X R E. 0 R C. CH CO₂ I OH R. H H

Which of the following could act as one of the substrates in a reaction catalyzed by a glycosyltransferase? Choose one or more: A. GalNAc ☐ B. galactose C. UDP-GalNAc D. GDP-Mannose