Sucrose vs Glucose
Glucose and sucrose are categorized as carbohydrates. Carbohydrates are a group of compounds which are defined as “polyhydroxy aldehydes and ketones or substances that hydrolyze to yield polyhydroxy aldehydes and ketones.” Carbohydrates are the most abundant type of organic molecules on the earth. They are the source of chemical energy for living organisms. Not only this, they serve as important constituents of tissues. Carbohydrate can be again categorized into three as monosaccharide, disaccharides and polysaccharides. Monosaccharides are the simplest carbohydrate type. Monosaccharides are classified according to,
- The number of carbon atoms present in the molecule
- Whether they contain an aldehyde or keto group
Therefore, a monosaccharide with six carbon atoms is called a hexose. If there are five carbon atoms, then it is a pentose. Further, if the monosaccharide has an aldehyde group, it is called as aldose. A monosaccharide with a keto group is called a ketose.
Sucrose is a disaccharide. It is made up of combining glucose and a fructose molecule via a glycosidic bond. During this reaction, a water molecule is eliminated from the two molecules. Sucrose can be hydrolyzed back into the starting molecules when needed. This is a disaccharide, which we find commonly in plants. Glucose, which is produced from the photosynthesis in leaves, should be distributed to other growing and storing parts of the plant. And sucrose is the form of transporting. Therefore, in plants glucose is converted to sucrose in order to distribute them. We are familiar with sucrose in our day to day lives, as we are using that as table sugar. Sucrose is a white crystalline solid. It has a sweet taste, and it is readily soluble in water.
Glucose is a monosaccharide that contains six carbon atoms and an aldehyde group. Therefore, it is a hexose and an aldose. It has four hydroxyl groups and has the following structure.
Though it is shown as a linear structure, glucose can be present as a cyclic structure too. In fact, in a solution, majority of the molecules are in the cyclic structure. When a cyclic structure is forming, the -OH on carbon 5 is converted into the ether linkage, to close the ring with carbon 1. This forms a six member ring structure. The ring is also called a hemiacetal ring, due to the presence of carbon that has both an ether oxygen and an alcohol group. Because of the free aldehyde group, glucose can be reduced. Thus, it is called a reducing sugar. Further, glucose is also known as dextrose because, it rotates plane polarized light to the right.
When there is sunlight, in plant, chloroplasts glucose is synthesized using water and carbon dioxide. This glucose is stored and used as a source for energy. Animals and human obtain glucose from plant sources. Glucose level in human blood is regulated by homeostasis mechanism. Insulin and glucagon hormones are involving in the mechanism. When there is high glucose level in blood, it is called a diabetic condition. The measurement of blood sugar level measures the glucose level in blood. There are various means to measure the blood glucose level.
What is the difference between Sucrose and Glucose?
• Glucose is a monosaccharide and sucrose is a disaccharide.
• Glucose is participating in making sucrose by combining with a fructose.
• Molecular weight of sucrose is higher than that of glucose.
• Chemical formula of glucose is C6H12O6. Chemical formula of sucrose is C12H22O11.
• Glucose is a reducing sugar where as sucrose is a non reducing sugar.