Like the flukes, tapeworms are flatworms with bilateral symmetry. However, the gross appearance of the tapeworms is much different. They typically possess three major parts: the head or scolex, the neck region, and the proglottids. The head is mainly just for attachment to the intestinal wall. It may contain suckers, hooks, or grooves, depending on the species. The neck region is where the proglottids develop, which contain the reproductive organs. Like many of the flukes, each proglottid contains both male and female reproductive organs. Tapeworms can be long-lived and produce many eggs. The top image to the right shows the entire tapeworm of Taenia saginata having many proglottids. The image below shows one proglottid from T. saginata (stained with carmine).
Note that most diagnoses are based on finding eggs in the stool. Only rarely are proglottids seen, except after anti-helminthic treatment.
19. Centers for Disease Control and Prevention (CDC). "This photograph depicts an adultTaenia saginatatapeworm that was approximately 4-meters in length. Humans become infected by ingesting raw or undercooked infected meat. In the human intestine, the cysticercus develops over a 2-month period into an adult tapeworm, which can survive for years, attaching to, and residing in the victim’s small intestine." CDC Public Health Image Library (PHIL), 1986, https://phil.cdc.gov/Details.aspx?pid=526020. DPDx. "Taeniasis - Figure A: Mature proglottid of T. saginata, stained with carmine. Note the number of primary uterine branches (>12)." CDC.gov, 18 Dec 2017, https://www.cdc.gov/dpdx/taeniasis/index.html
