Summary
Monomers made of a sugar, a phosphate group and a nitrogenous base that link to form nucleic acids.
In depth
Each nucleotide has a pentose sugar, a phosphate and a nitrogenous base. Linked by phosphodiester bonds between the 3 prime carbon of one sugar and the 5 prime phosphate of the next, they form chains.
Free nucleotides also act as signals and energy carriers: ATP, GTP, cAMP, NAD and FAD.
Purines (adenine, guanine) have two rings and pyrimidines (cytosine, thymine, uracil) one. A nucleoside is the base plus sugar, and adding phosphates gives nucleotides. Beyond nucleic acids, nucleotides serve as ATP and GTP for energy, cAMP for signalling, and parts of NAD, FAD and coenzyme A.
Chargaff's rules, that A equals T and G equals C in double-stranded DNA, provided the clue to base pairing. Nucleotides are made de novo or recycled by salvage pathways; defects in purine salvage cause Lesch-Nyhan syndrome, and excess uric acid from purine breakdown causes gout.
Frequently asked questions
What is Nucleotides?
Monomers made of a sugar, a phosphate group and a nitrogenous base that link to form nucleic acids.
Which area of biology covers Nucleotides, and how advanced is it?
Nucleotides is one of the 51 topics in Biomolecules & Biochemistry. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Nucleic Acids, Carbon Chemistry, Carbohydrates.
Why does Nucleotides matter?
Antiviral and anticancer drugs such as acyclovir and 5-fluorouracil are nucleotide analogues that disrupt DNA or RNA synthesis.
Can you give an example of Nucleotides?
ATP is simply an adenine nucleotide with three phosphates.
What should I learn before Nucleotides?
Nucleotides is a Beginner topic, so no earlier topic is required. Other Beginner topics in Biomolecules & Biochemistry that pair well with it include Water Properties, Carbon Chemistry, Carbohydrates.
What topics are related to Nucleotides?
The closest topics to Nucleotides are Nucleic Acids, Carbon Chemistry, Carbohydrates, ATP Structure and Function. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Nucleotides?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Nucleotides. To practise the whole of Biomolecules & Biochemistry, use the Biomolecules & Biochemistry quiz.
How is Nucleotides different from Nucleic Acids?
Nucleotides: Monomers made of a sugar, a phosphate group and a nitrogenous base that link to form nucleic acids. Nucleic Acids: DNA and RNA, polymers of nucleotides that store and transmit genetic information. Read both side by side and note what each one explains.
How should I study Nucleotides step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Nucleic Acids and explain the difference aloud. Finally, take the Biomolecules & Biochemistry quiz and come back to this page for any question you miss.