DNA Structure, Function and Replication

What makes up the backbone of a DNA molecule?

• nitrogen bases

• sugars & phosphates

• genes & chromosomes

• RNA

What makes up the rungs (steps) of a DNA molecule?

• sugars & phosphates

• nitrogen bases

• sugars

• genes & chromosomes

If one strand of a DNA molecule has the following order of bases, what will be the correct order of bases on the complementary (matching) strand?

AATTGGCC

• AATTGGCC

• TTAACCGG

• GGCCAATT

• GACTGACT

Nitrogenous bases are joined by which type of bond?

• polar bonds
• strong hydrogen bonds

• covalent bonds
• weak hydrogen bonds

Cytosine always pairs with

• Adenine
• Thymine
• Uracil
• Guanine

The picture below shows the steps of DNA replication beginning with step one and ending with step three.

​Because you are reusing the old, or parent, DNA strand DNA replication is said to be

• Semi- Conservative

• Semi-discontinuous

• Continuous

• Fully-Conserveative

The picture below shows an enzyme unwinding and unzipping DNA.

​

​What is the name of this enzyme?

• DNA Helicase

• DNA Ligase

• DNA polyermase

• RNA Polymerase

Which enzyme is responsible for adding the free nucleotides to the replicating DNA? ​

• DNA Helicase

• DNA Ligase

• DNA polyermase

• RNA Polymerase

A nucleotide is made up of three parts:  which of these is not one of those parts?

• sugar
• phosphate
• amino acids
• base

What are the three components of a nucleotide?

• sugar, hydrogen, nitrogen base
• sugar, oxygen, nitrogen base
• sugar, phosphate, nitrogen base
• sugar, phosphate, protein