Question

what is the diffrence between nucleotide and nucleoside?

Answer 1

nucleotide consists of pentose sugar , nitrogen base and phosphate group . but necleoside is consist of only pentose sugar and nitrogen base (piridin and pirimidin)

Answer 2

Chemistry of DNA:
1. Phosphoric Acid
2. Pentose Sugar
3. Nitogenous Bases: They are of two types:
(i) Purins: Adenine, Guanine. and (ii) Pyramidines: Thymine, Cytosine, Uracil.

Nucleotides:

Phosphoric Acid + Pentose Sugar + Nitrogenous bases → Nucleotides

Phosphoric Acid + Pentose Sugar + Adenine → Adynylic Acid
Phosphoric Acid + Pentose Sugar + Guanine → Guanylic Acid
Phosphoric Acid + Pentose Sugar + Thymine → Thymidic Acid
Phosphoric Acid + Pentose Sugar + Cytosine → Cytidylic Acid
Phosphoric Acid + Pentose Sugar + Uracil → Uridylic Acid (RNA)

Nucleosides:

Pentose Sugar + Nitrogenous bases → Nucleosides

Pentose Sugar + Adenine → Adenosine
Pentose Sugar + Guanine → Guanosine
Pentose Sugar + Thymine → Thymidine
Pentose Sugar + Cytosine → Cytidine
Pentose Sugar + Uracil → Uridine (RNA)

Thus, basic diiference between Nucleotides and Nucleosides are that in Nucleosites phosphoric acid, pentose sugar and nitogenous bases react to form nucleotides while in Nucleoside only sugar and nitrogenous bases react to form nucleosides. (Pentose Sugar is also called deoxyribose sugar).