Which one of the following is not a Platyhelminthes?

By: Prof. Dr. Fazal Rehman Shamil | Last updated: February 3, 2024

·        Members of the phylum Platyhelminthes exhibit bilateral symmetry, meaning their bodies can be divided into two identical halves along a central axis.

·        Platyhelminthes have three germ layers (ectoderm, mesoderm and endoderm) during their embryonic development, which gives rise to different tissue types in their body.

·        These organisms lack a true body cavity (coelom), and their tissues are directly in contact with each other.

·        Platyhelminthes have incomplete digestive system. They have a single opening that serves as both their mouth and anus. Thus food enters and waste exits through the same opening.

·        Protonephridia are excretory structures used for osmoregulation and waste elimination. They help to maintain the balance of water and solutes in the body.

·        Platyhelminthes do not have dedicated circulatory or respiratory systems for the transport of gases or nutrients throughout their bodies. Gas exchange occurs across body surfaces.

·        Nerve ladder arrangement with ganglia (nerve cell clusters) and longitudinal nerves.

·        Asexual (e.g., fission, regeneration) and sexual reproduction (hermaphroditic or cross-fertilization).

·        They exhibit muscular body movement. Some flatworms use cilia for locomotion.

·        They are found in aquatic environments such as freshwater and marine and terrestrial habitats.

·        Many species are parasitic in nature, adapting to life within other organisms.

Tapeworms

Flukes

Cestoda

Oncosphere