Glucose

Glucose is a simple sugar (Monosaccharide) and an important source of carbohydrate in biology. The chemical mixture is C 6 H 12 O 6. Glucose is one of the main products from photosynthesis and cellular respiration. It is the primary source of cellular energy for an organism.The reason for glucose being the main source of energy for an organism can relate directly with how it reacts with amino acid proteins compared to other sugars.Glucose does not react directly with amino acid proteins in the process of glycation, it has less reaction with this, which other sugars tend to react a lot with. Rather glucose prefers to have a less reactive cyclic isomer reaction. This glycation of protein damages enzymes that are crucial to humans natural ability to digest, which is directly related to health complications, as in diabetes. On the other hand, glucose uses a process referred to as glycosylation, where glucose productively works with the enzymes in proper digestion of carbohydrates. This will then produce five different classes of end products of glycans. Glycans server multiple structural and functional roles in secreted and membrane proteins. There are two different forms of glucose, D-glucose and L-glucose. D-glucose is also known as dextrose and cellulose and starch are derived from this type when dehydrated, while L-glucose is an organic compound and is rarely found in nature and will not be able to be digested by humans.

Glycogen is the body's "glucose energy storage" mechanism and is less reactive than glucose itself. Glucose is by far the most common carbohydrate and classified as a monosaccharide, an aldose, a hexose, and is a reducing sugar. It is also known as dextrose, because it is dextrorotatory (meaning that as an optical isomer is rotates plane polarized light to the right and also an origin for the D designation. Glucose is also called blood sugar as it circulates in the blood at a concentration of 65-110 mg/dL (or 65-110 mg/100 ml) of blood. Glucose is initially synthesized by chlorophyll in plants using carbon dioxide from the air and sunlight as an energy source. Glucose is further converted to starch for storage

Ring Structure for Glucose: Up until now we have been presenting the structure of glucose as a chain. In reality, an aqueous sugar solution contains only 0.02% of the glucose in the chain form, the majority of the structure is in the cyclic chair form. Since carbohydrates contain both alcohol and aldehyde or ketone functional groups, the straight-chain form is easily converted into the chair form - hemiacetal ring structure. Due to the tetrahedral geometry of carbons that ultimately make a 6 membered stable ring, the -OH on carbon #5 is converted into the ether linkage to close the ring with carbon #1. This makes a 6 member ring - five carbons and one oxygen.
 * Steps in the ring closure (hemiacetal synthesis):**

1. The electrons on the alcohol oxygen are used to bond the carbon #1 to make an ether (red oxygen atom).

2. The hydrogen (green) is transferred to the carbonyl oxygen (green) to make a new alcohol group (green). The chair structures are always written with the orientation depicted on the left to avoid confusion. Carbon # 1 is now called the **anomeric carbon** The position of the -OH group on the anomeric carbon (#1) is an important distinction for carbohydrate chemistry. The **Beta position** is defined as the -OH being on the same side of the ring as the C # 6. In the chair structure this results in a **horizontal projection**. The **Alpha position** is defined as the -OH being on the opposite side of the ring as the C # 6. In the chair structure this results in a **downward projection**. The alpha and beta label is not applied to any other carbon - only the anomeric carbon, in this case # 1.
 * Hemiacetal Functional Group:**
 * Compare Alpha and Beta Glucose in the Chair Structures:**

glucose is also one of the 8 D-aldohexoses