A unique vascular connection between the digestive tract and liver is called

The hepatic portal system is a unique vascular connection between the digestive tract (intestines) and the liver. It is a specialised network of blood vessels that carries nutrient-rich blood from the digestive organs to the liver before it is
distributed to the rest of the body. Nutrients from the digested food are absorbed by the small intestine and transported through the hepatic portal vein to the liver. The liver processes and metabolises these nutrients, detoxifies certain substances, and regulates glucose levels before releasing the processed blood into the general circulation.

(1) Coronary circulation transports blood to and from cardiac musculature.

(3) The renal portal system is a unique vascular arrangement found in many vertebrates where the blood from the posterior part of the body circulates through the kidneys before returning to the heart. Renal portals system is absent in mammals.

(4) Hypophyseal portal system carries blood from the hypothalamus to the adenohypophysis (anterior pituitary gland).