What is basic unit of a sugar molecule?

Answer 1

If you mean sugar for coffee (like cane sugar), it's a disaccharide called sucrose, and it's made of glucose and fructose : β-D-fructofuranosyl-(2↔1)-α-D-glucopyranoside.

If you mean "sugars" more globally, the basic unit is any molecule of the form Cn(H2O)n (hence the name "carbohydrates"). They are more precisely of the form HCO-(HCOH)n-CH2OH (aldoses, like the glucose or the ribose, which is found in the DNA) or CH2OH-CO-(HCOH)n-CH2OH (ketoses, like the fructose). Now most of encountered sugars in nature are of the form C5(H2O)5 (like the ribose), or C6(H2O)6 (like the glucose and the fructose).

Answer 2

Monosaccharide

Answer 3

If you mean sugar for coffee (like cane sugar), it's a disaccharide called sucrose, and it's made of glucose and fructose : β-D-fructofuranosyl-(2↔1)-α-D-glucopyranoside.

If you mean "sugars" more globally, the basic unit is any molecule of the form Cn(H2O)n (hence the name "carbohydrates"). They are more precisely of the form HCO-(HCOH)n-CH2OH (aldoses, like the glucose or the ribose, which is found in the DNA) or CH2OH-CO-(HCOH)n-CH2OH (ketoses, like the fructose). Now most of encountered sugars in nature are of the form C5(H2O)5 (like the ribose), or C6(H2O)6 (like the glucose and the fructose).