The polarization of the animal body based on the position of the head and mouth is called marginality. There are five types of limitations in the animal body.
(i) Anterior end: The end of the animal where the head is is called the anterior end. This is called the oral edge.
(ii) Posterior end: The end opposite to the head of the animal is called the posterior end. called the paraoral edge.
(iii) Dorsal end: The upper surface of the animal’s body is called the dorsal end.
(iv) Ventral end: The bottom of the animal’s body is called the ventral end.
(v) Lateral end: The bottom of both sides of the animal body is called lateral end.