Online Biology Dictionary

Tapeworm heads Tapeworm heads ("scolices") with attached segments ("proglottids"). a: pork tapeworm, Taenia solium (note hooks allowing gut wall attachment); b: beef tapeworm, Taenia saginata, which lacks hooks ("unarmed scolex"). Enlarge

Taenia (/TEEN-ee-yuh/ or /TEEN-yuh/) is a genus that includes two important human parasites, the pork tapeworm, Taenia solium, and the beef tapeworm, Taenia saginata.

A tape worm is composed of:

  1. a head, or scolex, by which it attaches itself to the wall of the small intestine of its host; and
  2. a long chain of segments, or proglottids — typically a thousand or more – each of which may contain up to 100,000 eggs.

Eggs and gravid proglottids are passed in the feces of the host. When ingested, they hatch in the gut of the new host, invade the blood stream, and then encyst, primarily in muscle tissue. When a carnivore eats infected tissue, the encysted larvae complete the life cycle, by developing into mature tapeworms in the small intestine.


Biology Dictionary >>

Most shared on Macroevolution.net:

Human Origins: Are we hybrids?

On the Origins of New Forms of Life

Mammalian Hybrids

Cat-rabbit Hybrids: Fact or fiction?

Famous Biologists

Dog-cow Hybrids

Georges Cuvier: A Biography

Prothero: A Rebuttal

Branches of Biology

Dog-fox Hybrids