Here's a breakdown:

* DNA (Deoxyribonucleic acid): Each nucleotide in DNA is composed of:

* Deoxyribose sugar (a 5-carbon sugar)

* Phosphate group

* Nitrogenous base: Adenine (A), Guanine (G), Cytosine (C), or Thymine (T)

* RNA (Ribonucleic acid): Each nucleotide in RNA is composed of:

* Ribose sugar (a 5-carbon sugar)

* Phosphate group

* Nitrogenous base: Adenine (A), Guanine (G), Cytosine (C), or Uracil (U)

These nucleotides link together in long chains to form the DNA and RNA molecules, with the sequence of bases determining the genetic code.