Question

The tape worm needs another organism to reproduce.

Answer 1

In the tapeworm , the eggs are shed in the host bodies which is converted in to embryo  and that are usually goes into feces of the host. The eggs don't hatch until it reach in body of one of the host. This is because the larva of the tape worm have to take feed from the host and can not survive in the harsh environment so they find a suitable environment for them.

Tapeworms are usually hermaphroditic that means they have both male and female reproductive organs in each of proglottid  but in most of the species one worm need another one for fertilization.
There are many less number of specie of tapeworm in which self-fertilization occur while most of the time cross fertilization is necessary for the reproduction.

Answer 2

Tapeworms are parasitic flatworms that spend the adult phase of their lives as parasites in the gut of vertebrate animals like humans, pigs etc.

The tapeworms are hermaphrodites whose proglottids contain the male and female reproductive systems. Although fertilization is internal, most of the species undergo cross-fertilization that occurs in between two adjacent worms. However, self-fertilization also occurs in between the 2 proglottids or same proglottid in the same worm.

Many species of tapeworms shed the fertilized eggs which are usually excreted through the feces. The eggs develop into embryos and they do not hatch until they are taken in by a suitable intermediate host. The embryos migrate in the intermediate host and may develop into the larva or may be dormant as a cestode. After reaching the primary host, the cestode gets ingested in the internal organs of the host causing diseases like epilepsy etc.