Question

Write two advantages of the hepatic portal system?

Answer 1

Hint: Portal system or circulatory system is developed in many phyla for the tramsport of materials in the body. This system includes fluid tissue, the blood, which may circulate in tubes the blood vessels with definite walls or in spaces, the sinuses, without proper boundaries.
The circulatory system is said to be closed in the former case and open in the latter case.

Complete answer: There are three types of portal system Renal portal system, hepatic portal system, and hypophyseal portal system

The Hepatic Portal System- The hepatic portal system is a series of veins that carry blood from the capillaries of the stomach, intestine, spleen, and pancreas to capillaries in the liver.
It is part of the body's filtration system.
The hepatic portal system takes the absorbed nutrients from the digestive tract first to the liver to process them helps in waste drainage from the pancreas and venous drainage from the spleen.
It helps in neutralizing toxic material.

The hypophyseal portal system - a system of blood vessels that connects the hypothalamus and the anterior pituitary gland. The hypophyseal portal system allows for communication between these two structures by means of hormonal signaling

Renal portal system - Renal portal system is an arterial portal system, in which blood from the posterior body enters and passes on to the caudal vena cava. It is present in non-mammals like fishes, reptiles, bird, and amphibians
In mammals the heart is 4- chambered having two auricles and two ventricles.
There is neither sinus venosus nor truncus arteriosus.
The heart supplies oxygenated blood to all parts of the body

Note: The renal portal system is lacking in mammal it is found in all living vertebrates except for hagfish, lampreys, and mammals.