Platyhelminthes
The flatworms consist of simple soft-bodied invertebrate animals. They have no specialized circulatory and respiratory organs, which restricts them to having flattened shapes that allow oxygen and nutrients to pass through their bodies by
diffusion.
diffusion.
Tapeworm
Tapeworms lay eggs in decaying matter, once laid, if eaten, the eggs will develop into larvae inside the organism that ingested it. Liver Fluke Liver flukes are parasites. These flatworms occur inside living organisms inside their organs. They feed on blood. Adult flukes produce eggs which are passed into the intestine, and eventually produce more eggs and are passed onto other organisms. Planarian There are sexual and asexual planaria. Sexual planaria are hermaphrodites, possessing both testicles and ovaries. Thus, one of their gametes will combine with the gamete of another planarian. Each planarian transports its excretion to the other planarian, giving and receiving sperm. Eggs develop inside the body and are shed in capsules. Weeks later, the eggs hatch and grow into adults. Sexual reproduction is desirable because it enhances the survival of the species by increasing the level of genetic diversity. |