How can simple diagrams represent the structure of single nucleotides of DNA and RNA, using symbols for phosphates, pentoses, and bases?
How can simple diagrams represent the structure of single nucleotides of DNA and RNA, using symbols for phosphates, pentoses, and bases?
Answer
To represent the structure of single nucleotides of DNA and RNA using simple diagrams, specific symbols can be employed for the different components: phosphates, pentoses, and bases. Here’s how to illustrate these structures effectively:
Diagram Components
- Phosphate Group:
- Symbol: Represented by a circle.
- Position: Attached to the 5′ carbon of the sugar.
- Pentose Sugar:
- Symbol: Represented by a pentagon.
- Types:
- In DNA, the sugar is deoxyribose.
- In RNA, the sugar is ribose, which has an additional hydroxyl group (-OH) at the 2′ position.
- Nitrogenous Base:
- Symbol: Represented by a rectangle.
- Types:
- In DNA, the bases are adenine (A), thymine (T), guanine (G), and cytosine (C).
- In RNA, the bases are adenine (A), uracil (U), guanine (G), and cytosine (C).
Connections
- The nitrogenous base is attached to the 1′ carbon of the pentose sugar.
- The phosphate group is connected to the 5′ carbon of the sugar, while in a polynucleotide chain, it links to the hydroxyl group on the 3′ carbon of another nucleotide’s sugar.