Evolution and systematics

The name "Kinorhyncha" comes from the Greek words kinema (motion) and rhynchos (proboscis or snout). Kinorhyncha is considered either a class within the phylum As-chelminthes or a separate phylum with close relationships to aschelminth worms. However, the Kinorhyncha was later included as a class in the phylum Cephalorhyncha, established for four classes of Aschelminthes: Priapulida, Kinorhyncha, Loricifera, and Nematomorpha.

Treated here as a phylum, Kinorhyncha encompasses two orders, five suborders, 10 families, 15 genera, and about 150 species. The two orders are: Cyclorhagida (with families Zelinkaderi-dae, Antigomonidae, Cateridae, Semnoderidae, Centroderidae, Echinoderidae, Dracoderidae, and Cephalorhynchidae), and Homalorhagida (with families Pycnophyidae and Neocentro-phyidae). There is no fossil record for the Kinorhyncha.

Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

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