1. A nitrogenous base: This is the part that varies between nucleotides and gives them their unique properties. There are five main nitrogenous bases:
* Adenine (A)
* Guanine (G)
* Cytosine (C)
* Thymine (T) (found only in DNA)
* Uracil (U) (found only in RNA)
2. A sugar molecule: This provides the backbone of the nucleotide.
* Deoxyribose is the sugar found in DNA.
* Ribose is the sugar found in RNA.
3. A phosphate group: This is the negatively charged part of the nucleotide that links to the sugar molecule of the next nucleotide in the chain.
Here's how they form the DNA and RNA molecules:
* DNA: DNA is a double helix, meaning two strands of nucleotides are intertwined. The strands are held together by hydrogen bonds between the nitrogenous bases: A always pairs with T, and G always pairs with C.
* RNA: RNA is usually single-stranded, though it can fold into complex shapes. In RNA, A pairs with U, and G pairs with C.
So, while both DNA and RNA are made up of nucleotides, the difference in their sugar molecules and one of their nitrogenous bases gives them unique properties and functions.
