Definitions

Question 1

Commensalism

Answer 1

A type of symbiosis where two (or more) organisms from different species live in close proximity to one another, in which one member is unaffected by the relationship and the other benefits from it.

Question 2

Diarrhea

Answer 2

abnormal frequency and liquidity of fecal discharges.

Question 3

Dysentery

Answer 3

Any of various disorders marked by inflammation of the intestines, especially of the colon and attended by pain in the abdomen, tenesmus and frequent stools containing blood and mucus. Causes include chemical irritants, bacteria, protozoa or parasitic worms.

Question 4

Ectoparasite

Answer 4

A parasite that lives on the outside of its host rather than within the host’s body. Fleas and lice are examples.

Question 5

Endoparasite

Answer 5

Any parasite which lives in the internal organs of an animal, as the tapeworms, Trichina, etc.; opposed to ectoparasite.

Question 6

Eosinophilia

Answer 6

The formation and accumulation of an abnormally large number of eosinophils in the blood.

Question 7

Host, Definitive

Answer 7

The host in which a parasite reproduces sexually.

Question 8

Host, Intermediate

Answer 8

That host which harbors the immature, larval, or asexually reproducing forms of the parasite.

Question 9

Host, Reservoir

Answer 9

The host of an infection in which the infectious agent multiplies and/or develops, and upon which the agent is dependent for survival in nature; the host essential for the maintenance of the infection during times when active transmission is not occurring.

Question 10

Mutualisam

Answer 10

Symbiosis in which both populations (or individuals)gain from the association and are unable to survive without it.

Question 11

Parasitism

Answer 11

A type of symbiosis where two (or more) organisms from different species live in close proximity to one another, in which one member depends on another for its nutrients, protection, and/or other life functions.

Question 12

Symbiosis

Answer 12

A type of organism-organism interaction where one organism lives in intimate association with another.

Question 13

Virulence

Answer 13

The degree or ability of a pathogenic organism to cause disease.

Question 14

Autoinfection

Answer 14

1. Reinfection by microbes or parasitic organisms on or within the body that have already passed through an infective cycle, such as a succession of boils, or a new infective cycle with production of a new generation of larvae and adults, as by the nematode Strongyloides stercoralis or the cestode Hymenolepsis nana.
2. Self-infection by direct contagion as with parasite eggs passed in the infectious state transmitted by fingernails (anal-oral route), as with the pinworm, Enterobius vermicularis. Synonym: autoreinfection, self-infection.

Question 15

Vector

Answer 15

1. a carrier, especially the animal (usually an arthropod) that transfers an infective agent from one host to another.

Question 16

Bilharzia

Answer 16

Schistosoma. Used most often in Spanish-speaking countries.

Question 17

Parenchyma

Answer 17

the essential elements of an organ

Question 18

Schiz, Schizo

Answer 18

A combining form meaning divided or denoting relationship to division. Splitters.

Question 19

Schizogony

Answer 19

A form of asexual reproduction characteristic of certain sarcodines and sporozoa in which daughter cells are produced by multiple fission of the nucleus of the parasite (schizont) followed by segmentatin of cytoplasm to form separate masses arund each smaller nucleus.

Question 20

Schizont

Answer 20

The multinucleate stage or form in the development of certain sarcodines and sporozoa during schizogony.

Question 21

Scolex

Answer 21

The attachment organ of a tapeworm, or the head.

Question 22

Sporogony

Answer 22

Sporulation. In protozoa, sporulation involving multiple fission of a sporont (schizogony), resulting in theproduction of sporocysts and sporozoites.

Question 23

Sporozoite

Answer 23

The elongate, nucleated, motile infective stage resulting from sporogony in gregarine and coccidian protozoa. In malaria, the sporozoites of Plasmodium spp. are liberated from the oocysts in the mosquito, accumulate in the vector’s salivary glands, and are transferred to the definitive host by the bite of the infected mosquito.

Question 24

Strobila

Answer 24

The chain of proglottids constituting the bulk of the body of adult tapeworms; considered y some to include the entire body, including the head, neck and proglottids.

Question 25

Trophozoite

Answer 25

The active, motile, feeding stage of a protozoan organism, as contrasted with the nonmotile encysted stage.

Question 26

Xenodiagnosis

Answer 26

A method of animal inoculation using laboratory-bred bugs and animals in the diagnosis of certain parasitic infections when it is not possible to demonstrate the infecting orgamism in blood films. Originally used in the diagnosis of Trypanosoma cruzi (Chaga’s Disease).