Question

please answer all 7-11

7. Which is not true for enzymes:

A. The active site is a three dimensional crevice in the protein.

B. Enzymes produce a more negative value for ΔG.

C. Most substrates bind enzymes by forming multiple weak interactions.

D. The active site takes up only a small part of the enzyme’s volume.

8. What are the two types of cofactors associated with enzymes? (6 points)

9. Explain the function of the following substances in solid phase DNA synthesis. (8 points)

A. Dimethoxytrityl group (DMT)

B. I₂ (diatomic iodine)

10. Circle the statement that is not true for plasmids.

A. They can replicate independently of the host chromosomes.

B. They come from viruses that infect bacteria.

C. They are circles of DNA.

D. They may contain restriction sites.

11. Circle the statement that is not true for restriction endonucleases.

A. They are isolated from prokaryotes.

B. They are necessary for PCR.

C. They usually interact at palindromes.

D. Include EcoRI.

Answer 1

7).B. Enzymes produce a more negative value for ΔG.

The free energy of the product is the same as it would be without the enzyme. Thus, the enzyme does not affect the free energy of the reaction.

8.) coenzymes and prosthetic groups are  the two types of cofactors that interact with enzyme.

9.) A. The DMT prevents polymerization of the nucleoside during functionalization of the solid support resin.

B. iodine is commonly used as reagent for the oxidation of internucleotide triester linkages.

10.)B. They come from viruses that infect bacteria

Plasmids are present in bacterial cells, and they also occur in some eukaryotes. Plasmids carrying genes provide bacteria with genetic advantages, such as antibiotic resistance.

11). B. They are necessary for PCR.

Taq polymerase, primers, template DNA, and nucleotides (DNA building blocks) are the only ingredients needed for PCR.