Final answer:
Monosaccharides that reach the liver are primarily converted into glycogen, a complex carbohydrate used for energy storage.
Step-by-step explanation:
Monosaccharides arriving at the liver are mostly converted to glycogen. During the absorptive state, the liver cells take these simple sugars, primarily glucose, and through the intermediary molecule glucose-6-phosphate, store them as glycogen. This process is part of the body's way of managing energy: when there is excess glucose, it is stored for later use as this complex carbohydrate. If there is still more glucose after the glycogen stores are filled, it can be converted into fat, specifically triglycerides, in adipose cells. However, the primary path for excess glucose in the liver is the synthesis and storage of glycogen.