Question

Which of the following is a non-parasite form?
A) Leech
B) Plasmodium
C) Sea anemone
D) Tapeworm

Answer 1

Hint: When organisms derive food from other living organisms, it is called the parasitic mode of nutrition and the organisms that show this type of nutrition are called parasites. They live in, or, on the body of the host.

Complete answer:
A parasite receives its food from the host but gives no benefit to the host in return. A parasite harms the host usually. It may be a plant or an animal. Most of the diseases which affect mankind, his domestic animals and his crops are caused by parasites. Parasitic mode of nutrition is observed in several fungi, bacteria and a few plants and animals.

Now, look at the options that we are provided with.
A) Leeches are the ectoparasites with anterior and posterior suckers for locomotion and feeding. The body lacks head, parapodia and setae. For example – cattle leech is inhabiting freshwater ponds, streams and rivers. It feeds on the blood of cattle and man.
B) Plasmodium is a parasite that causes malaria disease.
C) Sea anemone is a marine and sedentary cnidarian. It does not show the parasitic mode or form of nutrition because it shows mutualism that is beneficial for both partners.
D) Tapeworms are the endoparasites in the alimentary canals of vertebrates. Example – Taenia is a digenetic tapeworm occurring in the small intestine of man. Its larvae occur in the muscles of pigs.

So, the correct answer is option (C) Sea anemone.

Note: Sea anemone found attached to the empty shell of gastropods occupied by a hermit crab. The anemone protects the crab from enemies with its stinging cells, in return, the anemone is carried out by the crab to new feeding grounds and gets pieces of dropping from the crab’s prey. This association, beneficial to both partners, is called mutualism.