Across
- 4. In a cestode life cycle, the hexacanth (6-hooked) embryo found in the egg.
- 8. Permanent reduction to zero of the worldwide incidence of infection caused by a specific agent as a result of deliberate efforts. Intervention measures are no longer needed.
- 9. An asexual reproducing stage of some protozoa. It reproduces by schizogony.
- 10. The nonmotile, parasitic form in the life cycle of some protozoans (family Trypanosomatidae, and especially genus Leishmania) that usually develops in the cells of vertebrate hosts and occurs as a minute, ovoid or spherical body with a prominent, rod-shaped kinetoplast and a rudimentary, internal flagellum arising from a basal body
- 11. A stage in the unicellular life cycle, typically of trypanosomes, where the flagellum is posterior of the nucleus, and connected to the cell body by a long undulating membrane.
- 15. Any organism that lives in or on another organism without benefiting the host organism; commonly refers to pathogens, most commonly in reference to protozoans and helminths.
- 16. Laying eggs in which the embryos have developed little or not at all. Seen, for example, in the nematodes Toxocara canis and Ancylostoma caninum.
- 17. The initial invasive stage of most of the Apicompexan protozoa.
- 21. Flattened, wing-like expansions of the cuticle of nematodes (cervical, caudal or lateral).
- 23. Parasites that live outside a host's body.
- 25. A form of reproduction in which an unfertilized egg develops in to a new individual.
- 27. The study of host-parasite relationships.
- 29. Single-celled, microscopic organisms that can perform all necessary functions of metabolism and reproduction. Some are free-living, while others parasitize other organisms for their nutrients and life cycle.
- 30. In the trematode life cycle, the miracidium will invade a snail, lose the cilia and develop into an elongated sac, called the ____________.
- 32. Swelling from fluid build-up caused by improper functioning of the lymph system.
- 33. A general term referring to the nematodes (roundworms), trematodes (flat worms, flukes), cestodes (tapeworms) and acanthocephalans (thorny-headed worms).
- 36. The string of proglottides which make up the "body" of a tapeworm.
- 40. A term for a symbiotic relationship in which partners are capable of living apart.
- 42. Host in which the sexual stages of the parasite mature. If there are no sexual stages in the life cycle, then the host is the host in the life cycle considered most important to humans.
- 43. A large fluid filled cyst containing larva of Echinococcus spp.
- 46. A single, evaginated scolex that is embedded in a small solid cyst that are typically found in small intermediate hosts such as arthropods (Cyclophyllidian tapeworms).
- 48. Second larval type in Pseudophyllidian tapeworms in which after the crustacean is eaten by freshwater fish and the procercoid is liberated, this larval stage develops in the muscles of the new host and possesses the characteristic scolex and is the only stage which is infective to final host.
- 49. A hardy, thick-walled stage of the life cycle of coccidian parasites. This is the stage that is shed in the feces of people infected with parasites such as Cyclospora and Cryptosporidium.
- 50. A stage in the life cycle of protozoa of the family Sarcocystidae (tissue-cyst-forming coccidia). In particular this is the term used to describe the merozoite which forms within the tissue cyst in the intermediate host (and rarely within the definitive host). This infectious stage rarely infects new cells within the intermediate host, rather it is the infectious stage for the definitive host.
- 51. Stage of trematode life cycle that the cercaria after invading the second intermediate host or attaching itself to vegetation, develop into.
Down
- 1. The ciliated larva of a trematode that developed in and hatched from the egg.
- 2. A protozoan in a feeding stage, as opposed to a reproductive or resting stage.
- 3. A type of intermediate host in which immature helminths may survive for indefinite periods but do not undergo development. Further parasitic development depends upon infection of the definitive host, which is usually by predation on the host.
- 5. A phagosome that has fused with a lysosome within the phagocyte.
- 6. Larva of Taenia multiceps which is a fluid filled cyst containing many invaginated scolecies.
- 7. Infestation of organs and tissues of vertebrates by larval dipterans (flies).
- 10. Any of a large genus of naked rhizopod protozoans with lobed pseudopodia and of wide distribution in fresh and salt water, and moist environments.
- 12. A disease that is native to a particular geographic region.
- 13. The motile, elongated, extracellular form in the life cycle of some protozoans (family Trypanosomatidae, and especially genus Leishmania) that is characterized by a single anterior flagellum and no undulating membrane.
- 14. One segment of the body (strobila) of a tapeworm.
- 18. An organism, such as an insect, that transmits a pathogen to the body of a host.
- 19. A protozoan cell, produced by a sporozoan by merogony, that may become either a meront or a gamont.
- 20. Waste matter eliminated from the bowels; excrement.
- 22. The study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems.
- 24. Condition in which the organism develops in an egg and hatches within the adult female. Thus a live motile organism emerges from the adult female. Seen, for example, in the nematode Dirofilaria immitis and in some sharks and snakes.
- 26. A vacuole within a cell that was formed during phagocytosis.
- 27. The larvae of Pseudophyllidian tapeworms in which after a crustacean ingests a ciliated coracidium, the procercoid develops in the body cavity of the crustacean.
- 28. Chitinous structures found in male nematodes, usually paired. They are inserted in the female genital opening during copulation.
- 31. The stage in the life cycle of some protozoa (Apicomplexa) which is destined to become a gamete (macro- or micro-).
- 34. Extra-intestinal stage of Toxoplasma that are found in in vacuoles muscle, liver, brain, and lung found in intermediate and definitive hosts. It is the invasive and proliferative stage of Toxoplasma.
- 35. The anterior end ("head") of the adult cestode, it is the hold-fast organ that anchors the worm in the GI tract.
- 37. In the trematode life cycle, it is the larval form (possessing an oral sucker) that develops from the sporocyst and gives rise to the cercariae in the snail host.
- 38. Larval stage in the cestode life cycle which is a fluid filled cyst containing an attached single invaginated scolex typically found in mammal intermediate hosts (cyclophyllidian tapeworms).
- 39. A syndrome brought on from long-term obstruction of lymphatic vessels that leads to engorgement and thickened skin. It causes disfigurement, often of the leg.
- 41. In the trematode life cycle, the larval trematode, which may or may not have a tail, depending on the species, and emerges from the snail.
- 44. Parasites that live inside a host's body.
- 45. Diseases spread between animals and people.
- 47. The specific organism no longer exists in nature or the laboratory.