Protozoa Flashcards
What are protozoa?
Protozoa are unicellular, eukaryotic, heterotrophic organisms that may be free-living or parasitic.
How do protozoa ingest food?
Protozoa ingest food through phagocytosis, often using pseudopodia or specialized structures like the cytostome.
What are the two main stages in the life cycle of protozoa?
The cyst stage (dormant and resistant) and the trophozoite stage (reproductive and disease-causing).
Where are protozoa typically found?
Protozoa are found in aquatic environments, freshwater, oceans, and even extreme conditions like hot springs. Some are free-living, while others are parasitic.
What is the primary mode of reproduction in protozoa?
Most protozoa reproduce asexually through binary fission, budding, or fission.
What are the four major groups of protozoa based on locomotion?
Mastigophora (flagellated)
Sarcodina (amoeboids)
Sporozoa (sporozoans),
Ciliophora (ciliated protozoans).
Give examples of Mastigophora.
Trypanosoma, Trichomonas, Giardia, Leishmania.
What is the function of the pellicle in protozoa?
The pellicle provides a definite shape to the cell and helps in locomotion.
What are Mastigophora or Flagellated protozoans?
Protozoans that are parasites or free-living, with flagella for locomotion, a cuticle or pellicle covering, and reproduction by longitudinal binary fission.
What are Ciliophora or Ciliated protozoans?
Aquatic protozoans that move actively using thousands of cilia.
What are Sarcodina or Amoeboids?
Protozoans living in freshwater, sea, or moist soil that move and capture prey using pseudopodia.
How do amoeboids reproduce?
By binary fission and cyst formation.
What is unique about the shape of Sarcodina?
They have no definite shape and lack a pellicle.
What are Sporozoa or Sporozoans?
Endoparasitic protozoans that lack specialized locomotory organs and reproduce through sporozoite formation.
Give examples of Sarcodina.
Amoeba, Entamoeba.
