DNA Replication

Front

According to the central dogma, what is the flow of genetic information in cells?

Back

DNA to RNA to protein

Front

Which enzyme replaces RNA nucleotides in a primer with DNA nucleotides? Options: DNA polymerase III, DNA polymerase I, primase, helicase.

Back

DNA polymerase I

Front

In E. coli, which enzyme catalyzes the elongation of a new DNA strand in the 5’ to 3’ direction?

Back

DNA polymerase III

Front

A new DNA strand elongates only in the 5’ to 3’ direction because:

• DNA polymerase begins adding nucleotides at the 5’ end of the template
• The polarity of the DNA molecule prevents addition of nucleotides at the 3’ end
• Replication must progress toward the replication fork
• DNA polymerase can add nucleotides only to the free 3’ end

Back

DNA polymerase can add nucleotides only to the free 3’ end

Front

What is the function of topoisomerase?

Back

relieving strain in the DNA ahead of the replication fork

Front

What is the role of DNA ligase in the elongation of the lagging strand during DNA replication?

Back

It joins Okazaki fragments together

Front

The enzyme that carries out the function described above is:

Primase

,

Topoisomerase

,

DNA Polymerase I

,

DNA Polymerase III

Back

Primase

Front

Which enzyme unwinds the double helix strand of DNA during DNA replication?

Back

DNA helicase

Front

What relieves overwinding strain ahead of replication forks by breaking, swivelling, and re-joining DNA strands?

Back

Topoisomerase

Front

Which of the following joins the Okazaki fragments together?

• DNA helicase
• Topoisomerase
• DNA ligase
• DNA Polymerase III

Back

DNA ligase