Question

Platyhelminthes are triploblastic animals.
A. True
B. False

Answer 1

It is a multicellular animal which comprises three embryonic cell layers. It is seen in all multicellular organisms except certain vertebrates.

Complete step by step answer:
First we should know about Platyhelminthes to answer this question. Phylum Platyhelminthes is part of the Animalia Kingdom. 13,000 animals are found in this phylum. The species are considered as flatworms as well. These are acoelomate, possessing multiple types of free-living and parasitic life.
The given statement is true that platyhelminthes is considered as triploblastic because it has body tissues which derived three germ layers and they are endoderm, ectoderm and mesoderm which are found in all multicellular organisms except in sponges and cnidarians. Hair, brain, spinal cord and eye lens, etc. are created by Ectoderm. Due to endoderm and ectoderm activity, differentiation of mesodermal cells occurs. Mesoderm creates the coelom, which is the cavity of the body. This species are diverse because there is a body cavity. In this cavity, the organs lie freely and they are shielded by the fluid surrounding them.
The given statement is not false because platyhelminthes has three germ layers i.e., ectoderm, endoderm, and mesoderm due to which it is considered as triploblastic.

Thus, the correct answer is TRUE.

Note:
Scientists assume that from the diploblastic organism, triploblastic species were produced and this occurred about 600 years ago. A mesoderm is absent from diploblastic cells. The inner layer that forms the gut is endodermis, while the outer layer is ectoderm which gives rise to nephridia, epidermal layer, and nervous tissues. Since they lack mesoderm, the diploblastic organism does not have a body cavity.