First, this arrangement allows the liver to regulate the distribution of nutrients to the rest of the body. This ensures a homeostasis thr9ugh recruitment of requisite biological pathways such as glycogenesis, oxidation, fatty acid synthesis, gluconeogenesis, etcetera.
Second, it allows the liver to remove toxic substances before the blood is circulated to the entire body. The liver is an effective detoxifier. It takes up toxic substances and converts them into harmless substances or makes sure they are released from the body.