Question

Which of the following is Pseudocoelomate.
(a) Leech
(b) Liver fluke
(c) Hookworm
(d) Jellyfish

Answer 1

Hint: An organism in which the body cavity that is not derived from the mesoderm, as in a true coelom, or body cavity. Mainly three types are found called Eucoelom, pseudocolor, and Acoelom.

Complete answer:
Pseudocoelomate animals have a pseudocolor (literally "false cavity"), which may be a fluid filled body cavity. Tissue derived from mesoderm partially lines the fluid filled body cavity of those animals. Thus, although organs are held loosely, they're not also organized as during acoelomate include. Aschelminthes are pseudocoelomates and in this Hookworms are pseudocoelomic.
Classification of animals is easy when considering their morphological characteristics. Accordingly, the presence and absence of a body cavity, as well as, the type of it have provided the scientists with the major criterion for classification.

Coelomates	Acoelomates	Pseudocoelomates
These animals possess body cavities that are lined by the mesoderm.	The body cavity is absent in these animals.	These animals possess a body cavity but it is not lined by the mesoderm. The mesoderm is present in patches In these animals between ectoderm and endoderm.
Chordates, Annelids, Arthropod, Echinoderms	Platyhelminthes	. Aschelminthes

Coelom can support an immune system within the type of coelomocytes which will either be attached to the wall of the coelom or may float about in it freely. The coelom allows muscles to grow independently of the body wall — this feature is often seen within the alimentary canal of tardigrades which is suspended within the body within the mesentery derived from a mesoderm lined coelom.
So, the correct answer is (c) Hookworm.

Note: The pseudocoelomate phyla include Gastrotricha, Rotifera, Nematoda, Nematomorpha, Kinorhyncha, Loricifera, Acanthocephala.
- Major examples of coelomate animals include mollusks, arthropods, echinoderms, and chordates.
- The acoelomate phyla include Placozoa, Porifera, Cnidaria, Ctenophora, Platyhelminthes, Mesozoa, Nemertea, Gnathostomulida