What is the basic structural difference between glucose and fructose?

OR

Write the products obtained after hydrolysis of lactose.

Glucose is an aldose it has aldehydic group while fructose is a ketose containing keto group.

OR

Lactose is sugar that is made up of two smaller sugars: glucose and galactose. It is known as a disaccharide and on hydrolysis it will give one unit of glucose and one unit of galactose.