Several students have been practicing drawing their models of nucleotides. Whose model do you think is most consistent with the actual chemical structure of nucleotides

I can provide guidance on what the chemical structure of nucleotides looks like and what features should be included in an accurate representation.

A nucleotide is composed of three main components:

1. Phosphate Group (PO4): This is a phosphate molecule, often represented as a single phosphorus atom bonded to four oxygen atoms.
2. Sugar Molecule: In DNA, the sugar is deoxyribose, and in RNA, it is ribose. The sugar is a five-carbon ring.
3. Nitrogenous Base: There are four possible nitrogenous bases in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G). In RNA, uracil (U) replaces thymine.

A simplified representation might look like this:  

Phosphate

    |

    O

   / \

   O  P-OH

   \ /

    O

    |

    / \

   |  |

  --5'  '3--

   Sugar

   |

  /  \

Base  Base

Note that the exact structure of the sugar and the specific nitrogenous base will vary between adenine (A), thymine (T), cytosine (C), guanine (G), and uracil (U). The linkage between the sugar and the phosphate group occurs at the 5' carbon of the sugar.

When evaluating drawings, you'd want to check if these key components are present and positioned correctly. It's also important to ensure that the representation accurately reflects the specific nitrogenous base associated with the nucleotide.