* Poly: Means "many" or "multiple".
* Nucleotide: The basic building block of DNA and RNA. A nucleotide consists of three parts:
* Sugar: Deoxyribose in DNA, Ribose in RNA
* Phosphate group: A negatively charged molecule
* Nitrogenous base: Adenine (A), Guanine (G), Cytosine (C), Thymine (T) in DNA, or Uracil (U) in RNA
The long chain formation:
1. Nucleotides link together: Nucleotides connect via a sugar-phosphate backbone. The phosphate group of one nucleotide attaches to the sugar of the next nucleotide.
2. Repeating units: This creates a long chain of repeating sugar-phosphate units with nitrogenous bases sticking out like rungs on a ladder.
3. Polynucleotide: Due to the multiple, linked nucleotides, the entire chain is called a polynucleotide.
In essence: DNA is a polynucleotide because it's a polymer, a large molecule made up of many smaller repeating units (nucleotides).
