Structure of Nucleotides

Question 1

What are the two most common nucleic acids?

Answer 1

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)

DNA stores genetic information, while RNA has several functions in protein synthesis.

Question 2

What are nucleotides?

Answer 2

Monomeric structures that form nucleic acids

Nucleotides are analogous to amino acids in proteins.

Question 3

What is the primary function of DNA and RNA?

Answer 3

Store and transmit genetic information

This information determines the amino acid sequence of proteins.

Question 4

What are the components of nucleotides?

Answer 4

Base, monosaccharide (sugar), and phosphoric acid

Nucleotides are the building blocks of nucleic acids.

Question 5

What type of sugar is found in RNA?

Answer 5

D-ribose

D-ribose is a five-membered furanose ring.

Question 6

What type of sugar is found in DNA?

Answer 6

2-deoxy-D-ribose

This sugar differs from ribose at carbon 2 with a -H instead of –OH.

Question 7

What are the two purines found in both DNA and RNA?

Answer 7

Adenine (A) and Guanine (G)

Purines consist of two fused rings.

Question 8

Which pyrimidine is found only in DNA?

Answer 8

Thymine (T)

Thymine has an extra methyl group compared to uracil (U), which is found in RNA.

Question 9

Which pyrimidine is found only in RNA?

Answer 9

Uracil (U)

Uracil replaces thymine in RNA.

Question 10

What is a nucleoside?

Answer 10

Base covalently bonded to ribose or 2-deoxyribose

The bonding occurs at the anomeric carbon.

Question 11

How is guanosine formed?

Answer 11

By bonding guanine to ribose

This occurs through a condensation reaction.

Question 12

What forms a nucleotide?

Answer 12

A nucleoside bonded to phosphoric acid

For example, guanosine becomes guanosine 5’-monophosphate.

Question 13

What is the structure of D-ribose?

Answer 13

A five-membered furanose ring

D-ribose is a sugar present in RNA.

Question 14

What is the difference between ribose and 2-deoxyribose?

Answer 14

2-deoxy-D-ribose has -H instead of –OH at carbon 2

This structural difference is significant for the functions of DNA.

Question 15

What are the four main bases found in nucleic acids?

Answer 15

• Adenine (A)
• Guanine (G)
• Cytosine (C)
• Thymine (T) or Uracil (U)

Thymine is found only in DNA, while uracil is found only in RNA.

Question 16

True or False: All types of RNA have a similar structure.

Answer 16

True

RNA exists in several forms with similar structural features.