Protozoans

definitive host

the host in which the sexual reproduction of a parasite takes place

intermediate host

Host from which the larvae derive their nourishment

apical complex

a group of organelles specialized for entering host cells and tissues

Plasmodium

causes malaria

Giardia

a flagellate protozoa with an adhesive disk for attaching to the small intestine

Toxoplasma gondii

a apicomplexan protozoa with a definitive host in cats; can alter its hosts behavior to increase risk-taking and ensure the completion of its life cycle

Naegleria fowleri

an ameboid in which a human is an accidental host; associated with freshwaters in lakes; kills host within 3-7 days of CNS invasion

Vector

An organism that transmits pathogens from one host to another.

Protozoa

single-celled eukaryotic animals associated with pathogens; have unique structures and life cycles that make vaccine and drug development challenging

Trichomonas vaginalis

an anaerobic, flagellated protozoan parasite that is sexually transmitted

Trypanasoma brucei

African sleeping sickness, transmitted by tsetse fly; "antigenic variation" due to changes in dense homogeneous coat of variant surface glycoprotein (VSG) which switches during infection

kinetoplast

a mass of mitochondrial DNA lying close to the nucleus in some flagellate protozoa.

Pseudopod

A temporary, foot-like extension of a cell, used for locomotion or engulfing food

Pellicle

A firm, flexible coating outside the plasma membrane found in some protists

selective toxicity

A drug that kills harmful microbes without damaging the host

scientific name

The name given to each species, consisting of its genus and its species label; knowing how to write this correctly gets me more points on my exam

Entamoeba histolytica

protist that causes causes amoebic dysentery

accidental host

one that can serve as a host, but is not the usual host in the parasites' life cycle

Reservoir host

The organism that becomes infected by a pathogen and serves as a source of transfer of the pathogen to others

Zoonosis

An infectious disease that is transmissible from animals to humans.

disease ecology

study of the interaction of the behavior and ecology of hosts with the biology of pathogens

Flagella

whiplike tails found in one-celled organisms to aid in movement

adhesive disk

cellular structure Giardia uses to latch onto the small intestine

variable surface glycoproteins (VSGs)

an antigen on Trypanasomas that uses a quorum sensing mechanism to change and evade the immune system

Excystment

escape from cyst to metabolically active, motile form (trophozoite)

Encystment

The ability to form cysts, or dormant forms surrounded by a resistant outer covering. Important for parasitic forms in order to survive while moving between hosts.

Trophozoite

motile feeding stage of protozoa

virulence factors

traits of a microbe that promote pathogenicity

Malaria virulence factors

hides from immune system in red blood cells and liver, induces bite me factor to compete life cycle

Balantidium coli

the only ciliate that parasitizes humans and causes dysentery

Cyclospora

feces contaminated food. parasite that causes gastroenteritis. watery diarrhea, cramps, fever; most commonly spreads via raspberries

Cryptosporidium parvum

very chlorine-tolerant fecal-orally transmitted protist; causes diarrhea

Apicomplexans

An obligately parasitic protozoan, that cannot survive outside of host cells. Usually features an apical complex

Flagellated Protozoans

protist belonging to an entirely or mostly heterotrophic lineage with no cell wall and one or more flagella

Amoeba

A type of protist characterized by great flexibility and the presence of pseudopodia.

Neglected Tropical Diseases

Diseases that affect people primarily in the poorest areas of the world in which housing, sanitation, and water supplies are deficient.