Nucleotides and Nucleic Acids MCQ - Practice Questions with Answers

Nucleotides 

• Nucleotides are the monomer units of nucleic acids.
• A nucleotide is made up of nucleoside and phosphate group.
• A nucleoside is made up of 5 carbon pentose sugar and nitrogenous base.
• There are two types of nitrogenous bases: purine and pyrimidine.
• Purines have a double ring structure. There are two types of purines - adenine and guanine
• Pyrimidines have a single ring structure.There are three types of pyrimidines - thymine, cytosine, and uracil.
• A nitrogenous base is attached to the pentose sugar at the C-1 via N-glycosidic bond. It is a covalent bond.
• The phosphate group is attached to the C-5 via phosphoester bond.

Functions of nucleotides:

• These form the nucleic acids - DNA and RNA.
• These are components of coenzymes, nonprotein organic molecules that facilitate enzymatic reactions.
• ATP (adenosine triphosphate) is a nucleotide that supplies energy for synthetic reactions and for various other energy-requiring processes in cells.

 A Nucleotide showing Glycosidic and Ester bonds at C-1 and C-5 respectively