Protozoa and Helminths

• What type of metabolism do protozoa use?

  Heterotrophic
• Protozoa obtain energy from organic carbon
• Algae are photoautotrophic and obtain energy from light.
• What type of metabolism do molds use?

  Saprophytic
• Protozoa predators consume other unicellular organisms such as bacteria, algae, fungi, and other protozoa
• Arrange the stages of the protozoa life cycle in the correct order:

  1️⃣ Cysts

  2️⃣ Excystation

  3️⃣ Trophozoites

  4️⃣ Encystation
• What is the role of cysts in the protozoa life cycle?

  Dormant stage
• Trophozoites are active, motile cells in the protozoa life cycle.
• Protozoa life cycles can be direct or indirect
• Match the protozoa with their type of life cycle:

  Entamoeba histolytica ↔️ Direct

  Plasmodium spp. ↔️ Indirect
• What is the primary basis for classifying protozoa parasites?

  Mode of motility
• Amoeba move by pseudopods
• Match the protozoa group with its method of motility:

  Flagellates ↔️ Flagella

  Ciliates ↔️ Cilia

  Sporozoa ↔️ Non-motile
• Which protozoa is responsible for malaria?

  Plasmodium spp.
• Malaria is transmitted by Anopheles mosquitoes.
• What is the role of sporozoites in the Plasmodium life cycle?

  Infect hepatocytes
• 1. vivax and P. ovale produce dormant hypnozoites
• Match the host type with its role in the Plasmodium life cycle:

  Human ↔️ Intermediate host

  Mosquito ↔️ Definitive host
• How does a merozoite attach to a red blood cell in Plasmodium falciparum?

  TRAP protein
• The asexual blood stage of Plasmodium falciparum is highly synchronised
• What is the role of PfEMP in Plasmodium falciparum pathogenicity?

  RBC membrane remodelling
• Infected red blood cells bind to endothelial cells to avoid clearance by the spleen.
• Malaria is most prevalent in tropical and subtropical regions.
• Match the Plasmodium species with its primary geographic region:

  1. falciparum ↔️ All shaded areas
  2. vivax ↔️ Asia and Latin America
  3. ovale ↔️ Sub-Saharan Africa
• Which drug inhibits hemozoin formation in malaria treatment?

  Quinine
• Primaquine is specifically used to kill dormant hypnozoites
• The RTS,S/AS01 vaccine against malaria targets the circumsporozoite protein (CSP).
• Arrange the steps in the life cycle of Giardia intestinalis:

  1️⃣ Cysts are activated by stomach acid

  2️⃣ Trophozoites emerge

  3️⃣ Trophozoites attach to small intestine epithelium
• Entamoeba histolytica causes the intestinal infection called amebiasis
• Extra-intestinal Entamoeba histolytica can invade blood vessels and move to the liver, lungs, or brain.
• What is the primary diagnostic method for Entamoeba histolytica?

  Microscopic stool examination
• Helminths are multicellular eukaryotic organisms that are typically macroscopic
• Adult helminths can be monoecious (hermaphroditic) or dioecious (two sexes).
• What type of eukaryotes are helminths?

  Multicellular
• Helminths are exclusively parasitic and do not have free-living stages.

  False
• Helminths are grouped by their morphology
• Match the major groups of helminths with their descriptions:

  Platyhelminths ↔️ Flatworms

  Nematodes ↔️ Roundworms

  Trematodes ↔️ Flukes

  Cestodes ↔️ Tapeworms
• What are soil-transmitted helminths associated with?

  Poor sanitation
• Ascaris lumbricoides eggs hatch in the small intestine and then mature in the lungs.

  False
• Ascaris lumbricoides infections can be treated with albendazole