PetriKey

Parasite

Toxoplasma gondii

Cat-associated apicomplexan clue

TOK-soh-plaz-muh GON-dee-eye

parasiteprotozoaapicomplexancatcongenital

High-yield clue

Cat definitive-host vocabulary + tissue cysts + congenital association.

Overview

An apicomplexan parasite used to teach cat definitive-host vocabulary, tissue cysts, and congenital/opportunistic infection concepts.

Classification

  • Protozoan
  • Apicomplexan
  • Tissue cyst concept

Lab & identification clues

  • Serology vocabulary
  • PCR concept
  • Tachyzoite/bradyzoite life-stage terms

Associations

  • Congenital infection vocabulary
  • Immunocompromised-host encephalitis vocabulary
  • Foodborne tissue cyst framing

Commonly confused with

  • Plasmodium species
  • Cryptosporidium

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource