Question

Cysticercus is the larvae of
(a) Liver fluke
(b) Tapeworm (Taenia)
(c) Ascaris
(d) Mollusca

Answer 1

Hint: A larva is a stage of development in an organism before undergoing metamorphosis into adults. It has unique structures which makes it different from the adult form and prefer a different diet from adults.

Complete answer:
Cysticercus is the larva of a tapeworm. It is a name given to the young tapeworms which are small and resemble a bladder that is sac-like and is known as a bladder worm. It consists of fluid inside the scolex which is the main body of the large and develops from the eggs which get ingested by the host which include pig and cattle. It causes a tissue infection which is known as cysticercosis. During this infection, they settle in the muscles of the host. It is transferred to humans when they eat raw and cooked pork or beef. It contaminates the host and the larva grows into adult worms inside their intestine. The eggs get eaten by humans through contaminated foodstuffs accidentally. The eggs hatch inside the body and move towards the muscles and brain which leads to an infection of a serious medical condition known as neurocysticercosis which leads to epilepsy.

Additional information:
Liver fluke: Fasciola hepatica causes the liver rot of sheep. It is a leaf-shaped worm which is also known as a liver fluke and is about 2 to 4 centimetres long. It grows in the liver of various animals and lays eggs which are passed through the bile duct and are excreted in the faeces.
Ascaris: Ascaris is a small intestinal roundworm that is a parasitic nematode and affects the human causing the disease ascariasis. They deposit their eggs in the faeces and soil. The plant with their eggs can infect any organism which consumes them.
Mollusca: Molluscs are invertebrates with a whole or part enclosed calcium carbonate shells which are a soft mantle covering the body. Molluscs can live in all habitats except air. They are mostly marine, bivalves, and gastropods including freshwater species. They are found on rocky, sandy, and muddy areas and can burrow, crawl, and can swim freely.

So, the correct answer is 'Tapeworm (Taenia)’.

Note:
Tapeworm size can grow up to the size of the school bus. The longest size found was 90 feet. They lived around 200 million humans around the world. Fluke, which is an example of Platyhelminthes, can produce up to 500,000 embryos. Molluscs are known for their self-defence. Molluscs have around 80000 of their species alive.