Glucose is a simple hexose (six carbon atom) sugar. It is a major source of energy within the cell. During respiration, glucose is broken down to produce ATP.
$$\alpha$$-glucose and $$\beta$$- glucose are two isomers of glucose. They differ only in the position of the OH group on their first carbon atom. In one, the OH group points up, and in the other, it points down.
We can remember the position of the OH group using the mnemonic ABBA - alpha below, beta above.
$$\alpha$$-glucose forms polymers with a curved structure. This is due to the angle of the bond between two glucose molecules. These polymers include starch and glycogen.
$$\beta$$-glucose forms polymers with a linear structure. Alternate glucose molecules must rotate in order to fit together. Cellulose is made of $$\beta$$-glucose.