What is the total number of carbon atoms present in a sugar molecule of $RNA$ nucleotide?

On hydrolysis,which of the following carbohydrates gives glucose only?

$A$ carbohydrate $(A)$,when treated with dilute $HCl$ in alcoholic solution,gives two isomers $(B)$ and $(C)$. $B$ on reaction with bromine water gives a monocarboxylic acid '$Z$',and '$C$' is a ketohexose. What is $A$?

What is the monomer of cellulose?

Name the sugar present in milk. How many monosaccharide units are present in it? What are such oligosaccharides called?

Which one acts as a non-reducing sugar?