Animals studied Table 19 Highest Level of Type of organizati

Table 19. Highest Level of Type of organization germ layers \"asymmetry (sponges) Cell Noa Cnidaria Pha An tea cnidarians-- jellyfish, hyvha. Radar 4 nerve Platyhelminthes ema toda (flatworm) Hoda Nematoda worms) bila uran 3 and have germ Germ associated with gastrulation. Note that deuterostomes product of developmental in which leads threetissue layers

Solution

6. Digestive system also known as alimentary canal has two openings , one mouth and the other one is anus. One is used to feed the food in , the other one propels the waste outside the body.

Complex organisms such as mammals, human beings possess digestive system.

Gastrovascular cavities are pouches where the food is digested in. It has only one opening that serves as both mouth and anus.

Digestive system is advantageous in contrast to Gastrovascular cavity as it has 2 ends, so the food ingested inside the body, stays there for a longer time and the nutrients can be better absorbed by the body. Even the larger food particles can be ingested in. This is not possible in Gastrovascular cavity . So digestive system is better.

Simple organisms such as cnidaria possess this.