TRB PG Assistant - Structure and life history of helminth parasites – Fasciola, Taenia, Wuchereria, Ascaris Question Bank with Options

1. The phenomenon of nocturnal periodicity in microfilariae of Wuchereria bancrofti is thought to be related to:

A) Host body temperature and oxygen levels

B) Lunar cycles

C) The feeding habits of the mosquito vector

D) The worm's own internal clock

2. The terminal part of the digestive tract in Fasciola hepatica is:

A) Absent

B) A simple anus

C) A cloaca

D) A coiled intestine

3. Which of the following helminths has a life cycle that does NOT involve an intermediate host for humans to become infected?

A) Fasciola hepatica

B) Taenia solium

C) Wuchereria bancrofti

D) Ascaris lumbricoides

4. The cuticle of Ascaris lumbricoides is shed and replaced multiple times during its life cycle. This process is called:

A) Metamorphosis

B) Ecdysis (molting)

C) Budding

D) Regeneration

5. The 'bladder worm' stage of Taenia species is also known as:

A) Cercaria

B) Sporocyst

C) Cysticercus

D) Redia

6. Which of the following helminths is known for its pseudocoelom (false body cavity)?

A) Fasciola hepatica

B) Taenia solium

C) Wuchereria bancrofti

D) All of the above

7. The liver fluke, Fasciola hepatica, belongs to which class of Platyhelminthes?

A) Cestoda

B) Trematoda

C) Turbellaria

D) Monogenea

8. The uterus in a gravid proglottid of Taenia species primarily contains:

A) Ova

B) Oncospheres

C) Developing embryos

D) Yolk cells

9. The development of microfilariae into infective larvae within the mosquito vector of Wuchereria bancrofti is an example of:

A) Direct development

B) Indirect development with biological transmission

C) Asexual reproduction

D) Parthenogenesis

10. Which of the following is NOT a typical feature of the adult Ascaris lumbricoides?

A) Cylindrical body shape

B) Separate sexes (dioecious)

C) Presence of suckers

D) Complete digestive system

11. The disease caused by Wuchereria bancrofti is primarily characterized by:

A) Gastrointestinal bleeding

B) Blockage of the lymphatic system

C) Damage to the nervous system

D) Liver damage

12. The term 'proglottid' refers to a segment of which type of helminth?

A) Nematode

B) Trematode

C) Cestode

D) Acanthocephalan

13. What is the infective stage for the intermediate host (snail) of Fasciola hepatica?

A) Adult fluke

B) Sporocyst

C) Miracidium

D) Cercaria

14. Pulmonary symptoms, such as cough and wheezing, can occur during which phase of Ascaris lumbricoides infection?

A) When the adult worms are in the intestine

B) During the larval migration through the lungs

C) Immediately after ingesting the infective eggs

D) During the egg-laying phase

15. The presence of a genital pore is characteristic of which part of the Taenia tapeworm?

A) Scolex

B) Neck

C) Immature proglottid

D) Mature and gravid proglottid

16. Which larval stage of Fasciola hepatica develops within the snail and reproduces asexually?

A) Miracidium

B) Sporocyst and Redia

C) Cercaria

D) Metacercaria

17. A characteristic feature of the Taenia scolex is the presence of:

A) A pharynx and esophagus

B) Suckers and/or hooks for attachment

C) A complex digestive system

D) Cilia for locomotion

18. The lymphatic system is the primary site for adult Wuchereria bancrofti. However, larval stages (microfilariae) can be found in:

A) The liver and spleen

B) The blood, with nocturnal periodicity

C) The brain and spinal fluid

D) The muscles and subcutaneous tissues

19. What is the primary way humans acquire infection with Ascaris lumbricoides?

A) Eating raw fish

B) Drinking contaminated water with eggs

C) Contact with infected soil

D) Inhaling dust containing eggs

20. The intestinal lumen of the definitive host is the habitat of which adult helminth?

A) Fasciola hepatica

B) Taenia solium

C) Wuchereria bancrofti

D) All of the above

21. The cercaria of Fasciola hepatica possesses a tail and is motile. What is its fate after leaving the snail?

A) It directly infects the definitive host.

B) It encysts on vegetation to form a metacercaria.

C) It develops into a redia.

D) It burrows into the snail's tissues.

22. Which of the following helminths is known for causing 'swimmer's itch' as a human health problem?

A) Fasciola hepatica

B) Taenia solium

C) Schistosoma species (not in this list, but a common fluke example)

D) Wuchereria bancrofti

23. What is the primary target organ for the adult Ascaris lumbricoides?

A) Liver

B) Lungs

C) Small intestine

D) Heart

24. The filariform larva of Wuchereria bancrofti is characterized by:

A) A blunt tail and a short esophagus

B) A sharp, pointed tail and a long esophagus

C) The presence of a pharynx

D) The ability to penetrate the skin directly

25. The gravid proglottids of Taenia species contain:

A) Sperm and ova

B) Developing oncospheres within eggs

C) The scolex

D) Digestive enzymes

26. Which of the following statements about the life cycle of Taenia saginata (beef tapeworm) is true?

A) It uses pigs as intermediate hosts.

B) Humans become infected by ingesting undercooked beef containing cysticerci.

C) The adult worm resides in the lungs.

D) It is transmitted by mosquito bites.

27. The reproductive system of Fasciola hepatica is characterized by:

A) A single set of male and female organs

B) Separate male and female individuals

C) Hermaphroditism, with both male and female organs in each individual

D) Asexual reproduction only

28. In Fasciola hepatica, the miracidium is the larval stage that emerges from the egg and infects the snail. What is its primary characteristic?

A) It is non-motile and spherical

B) It possesses cilia for movement and an apical gland

C) It develops into a cercaria directly

D) It is the infective stage for the definitive host

29. The term 'cysticercosis' refers to an infection caused by which helminth parasite?

A) Fasciola hepatica

B) Wuchereria bancrofti

C) Taenia solium

D) Ascaris lumbricoides

30. What is the oncosphere in the life cycle of Taenia species?

A) The adult tapeworm

B) The larval stage in the intermediate host's muscle

C) The larval stage within the egg, which contains hooks

D) The infective stage for the definitive host

31. The infective larvae of Wuchereria bancrofti are transmitted by mosquitoes. What is the stage of the larva that infects humans?

A) Microfilaria

B) Third-stage larva (filariform larva)

C) First-stage larva (rhabditiform larva)

D) Second-stage larva

32. Which helminth parasite has a life cycle that typically involves two intermediate hosts?

A) Ascaris lumbricoides

B) Taenia solium

C) Fasciola hepatica

D) Wuchereria bancrofti

33. The proglottids are characteristic features of which group of helminths?

A) Trematodes

B) Cestodes

C) Nematodes

D) Acanthocephalans

34. Which of the following helminths is a trematode (fluke)?

A) Taenia solium

B) Wuchereria bancrofti

C) Ascaris lumbricoides

D) Fasciola hepatica

35. The adult Ascaris lumbricoides lives in the:

A) Bile ducts

B) Small intestine

C) Large intestine

D) Stomach

36. What is the primary mode of transmission for Ascaris lumbricoides?

A) Ingestion of contaminated water

B) Inhalation of airborne eggs

C) Bite of an infected insect

D) Consumption of undercooked meat

37. The life cycle of Ascaris lumbricoides involves a larval migration through the host's body. Which organs are typically involved in this migration before the worms reach the intestine?

A) Heart and kidneys

B) Lungs and liver

C) Brain and spinal cord

D) Spleen and pancreas

38. Ascaris lumbricoides is a large intestinal roundworm. What is the infective stage for humans?

A) Adult worm

B) Egg with developed larva (larvated egg)

C) Egg without larva (unembryonated egg)

D) Larval stage in soil

39. The characteristic symptom of chronic Wuchereria bancrofti infection is:

A) Jaundice

B) Elephantiasis

C) Anemia

D) Hepatitis

40. The microfilariae of Wuchereria bancrofti exhibit periodicity. What does this mean?

A) They are only present during the day

B) They are only present during the night

C) Their numbers fluctuate randomly

D) They are continuously present in equal numbers

41. What is the vector for Wuchereria bancrofti?

A) Housefly

B) Mosquito

C) Tick

D) Sandfly

42. Wuchereria bancrofti is a filarial worm responsible for lymphatic filariasis. In which part of the lymphatic system does the adult worm primarily reside?

A) Lymph nodes

B) Lymphatic vessels of the limbs and groin

C) Thoracic duct

D) Spleen

43. Which of the following is the definitive host for Taenia solium?

A) Pig

B) Cow

C) Human

D) Dog

44. In Taenia solium, the larval stage that develops in the intermediate host (pig) and is infective to humans is called:

A) Cercaria

B) Miracidium

C) Cysticercus

D) Onchosphere

45. The scolex of Taenia solium is equipped with structures for attachment. What are these structures?

A) Suckers only

B) Hooks and suckers

C) Cilia and adhesive glands

D) Antennae and mandibles

46. What is the characteristic shape of the adult Taenia solium (pork tapeworm)?

A) Leaf-like and dorsoventrally flattened

B) Elongated and cylindrical

C) Segmented and ribbon-like

D) Globular and unsegmented

47. The adult Fasciola hepatica resides in which organ of the definitive host (sheep or cattle)?

A) Intestine

B) Liver and bile ducts

C) Lungs

D) Blood vessels

48. Which stage of Fasciola hepatica is infective to the intermediate host, the snail?

A) Sporocyst

B) Redia

C) Cercaria

D) Metacercaria

49. In Fasciola hepatica, the ventral sucker is also known as the acetabulum. What is its primary function?

A) Absorption of nutrients from the host

B) Attachment to the host's tissues

C) Reproduction and gamete release

D) Excretion of waste products

Structure and life history of helminth parasites – Fasciola, Taenia, Wuchereria, Ascaris - Question Bank