The Structure of DNA

What is the main focus of molecular biology?

• Cellular respiration
• Molecular basis of biological activity
• Ecosystem dynamics
• Evolutionary biology

What is the main role of nucleic acids in cells?

• Energy storage
• Directing protein synthesis
• Waste removal
• Cellular respiration

Which of the following is the genetic material in most viruses?

• DNA
• RNA
• Proteins
• Lipids

Which molecule is known as the master blueprint for life?

• RNA
• DNA
• ATP
• Protein

What type of structure does DNA have?

• Single strand
• Double helix
• Triple helix
• Quadruple strand

What are the components of a nucleotide in DNA?

• Sugar, phosphate, and amino acid
• Sugar, phosphate, and nitrogenous base
• Sugar, lipid, and phosphate
• Sugar, protein, and base

Which nitrogenous bases are classified as purines?

• Adenine and thymine
• Guanine and cytosine
• Adenine and guanine
• Cytosine and thymine

How many rings do purine bases have in their chemical structure?

• One ring
• Two rings
• Three rings
• Four rings

Which bases are classified as pyrimidines?

• Adenine and guanine
• Cytosine and thymine
• Thymine and guanine
• Adenine and cytosine

How many hydrogen bonds link adenine and thymine?

• One
• Two
• Three
• Four