IB Biology 2.6 Quiz (DNA & RNA Structure) Extra

In nucleic acids, which type of bond links the 5-carbon sugars with an organic base?

• Peptide
• Covalent
• Hydrogen
• Phosphate

Which of the following nitrogenous bases is found in DNA, but is not found in RNA? 

• Uracil
• Adenine
• Thymine
• Guanine

Which of the following is not found in all nucleotide molecules? 

• Nitrogen base
• pentose (a 5-carbon sugar)
• phosphate group
• Adenine

The two strands of a DNA double helix are held together by:

• hydrogen bonds
• peptide bonds
• covalent bonds
• ionic bonds

Which one of the following proportions is true for DNA?

• A = C
• C = T
• T = A
• C > G

In DNA, adenine always pairs with:

• uracil
• thymine
• guanine
• cytosine

In RNA, adenine always pairs with:

• uracil
• thymine
• adenine
• gaunine

DNA is made up of a phosphate group, an organic base, and __________.

• a molecule of ATP
• a sugar
• an amino group
• glycerol

In the RNA molecule:

• adenine pairs with thymine 
• cytosine pairs with thymine
• guanine pairs with thymine 
• adenine pairs with uracil

Analysis of the DNA of an organism reveals that it is composed of 20% T (thymine). Based on this information, what would you predict the % C (cytosine) to be?

• 60%
• 30%
• 20%
• 10%