Many things are naturally sweet such as fruit and the sap of some kinds of trees and the juice of some plants. Through the process of photosynthesis sunlight acts on the chlorophyll, the green substance in the leaves causing carbon dioxide to chemically combine with water to form sucrose. Sucrose is what we know as regular table sugar. Sucrose can be chemically broken down into two other sugars - glucose and fructose. In plants, the two sugars are taken from the leaves and stored in other parts of the plant. Fruit is sweet because fructose is stored in the fleshy part of the fruit.
Figure 2: Brown Sugar Crystals
Bees carry the nectar of flowers which contain fructose and put it into the cells of the honeycomb. As the water evaporates the nectar thickens into honey. The juice from the sugar cane and the sap from certain trees such as the sugar maple are boiled to evaporate the water and produce thicker sweeter syrup. Sugar cane juice is boiled leaving behind molasses. Light molasses has high sugar content and as it sits it becomes darker, more concentrated and less sweet.