DNA Structure and Replication Quiz

What are the four nitrogenous bases in DNA?

• Adenine, Thymine, Cytosine, Deoxyribose

• Adenine, Thymine, Cytosine, Ribose

• Adenine, Thymine, Cytosine, Guanine

• Adenine, Thymine, Cytosine, Uracil

How many chromosomes are there in a human somatic cell?

• 46

• 64

• 23

• 92

What is the sugar molecule in DNA called?

• Fructose

• Glucose

• Deoxyribose

• Ribose

Which enzyme is responsible for unwinding the double helix during DNA replication?

• RNA Primase

• DNA Ligase

• DNA Polymerase

• Helicase

What is the function of DNA Ligase during DNA replication?

• Adds matching nucleotides to the new DNA strand

• Unwinds the double helix

• Replaces RNA primers with DNA nucleotides

• Joins the Okazaki fragments on the lagging strand

How many base pairs are there in human chromosome 1?

• 24 million

• 47 million

• 200 million

• 247 million

What is the main difference between DNA and RNA?

• DNA has ribose sugar, RNA has deoxyribose sugar

• DNA has adenine, RNA has guanine

• DNA contains thymine, RNA contains uracil

• DNA is single-stranded, RNA is double-stranded

What is the role of RNA Primase during DNA replication?

• Adds matching nucleotides to the new DNA strand

• Replaces RNA primers with DNA nucleotides

• Unwinds the double helix

• Lays down RNA primers for DNA polymerase to start replication

What is the function of DNA polymerase during DNA replication?

• Adds matching nucleotides to the new DNA strand

• Joins the Okazaki fragments on the lagging strand

• Replaces RNA primers with DNA nucleotides

• Unwinds the double helix

In a molecule of double-stranded DNA, the amount of Adenine present is always equal to the amount of

• cytosine
• guanine
• thymine
• uracil