Week 1-6

In a DNA molecule, one end has a free hydroxyl group, and one end has a free

• phosphate group.

• hydroxyl group.

• amino group.

• carboxyl group.

What type of bonds spontaneously form between two complementary strands of DNA?

• Hydrogen bonds

• Covalent bonds

• Phosphodiester bonds

• Polar covalent bonds

The term used to describe the arrangement of the individual strands in the double-stranded DNA molecule is

• parallel.

• antiparallel.

• tangential.

• divergent.

A DNA sequence is modified by replacing all guanine (G) bases with adenine (A) bases. What will be the effect of this change on the melting temperature (Tm) of the DNA?

• The Tm will increase.

• The Tm will remain the same.

• The Tm will decrease.

• The Tm change will be unpredictable.

DNA replication of the leading strand proceeds with the new daughter strand synthesized in which orientation?

• 5' to 3'.

• 3' to 5'.

• Discontinuously.

• Either 5' to 3' or 3' to 5'.

DNA polymerase adds nucleotides to:

• the 3' end of the primer

• the 5' end of the primer

• both ends of the primer

• neither end of the primer

Which of the following is the 3' end of DNA?

• 3' OH of growing DNA

• 5' end of RNA primer

• 5' OH of growing DNA

• 3' or 5' end of DNA

In DNA synthesis, where does replication begin and end?

• Origin of replication; end of the molecule

• Promoter; termination site

• Start codon; stop codon

• Start codon; termination site

An exonuclease will catalyze what type of reaction?

• Polymerization of nucleotides into long strands

• Separation of complementary DNA strands

• Dissociation of phosphodiester bonds at the ends of DNA molecules

• Formation of circular DNA molecules from linear ones

When an RNA molecule folds, adenine always base pairs with

• thymine

• cytosine

• uracil

• guanine