Protozoa

What domain do protozoa belong to?

Domain Eukarya.

What kingdom do protozoa belong to?

Kingdom Protista.

Are protozoa prokaryotic or eukaryotic?

Eukaryotic because they have a nucleus and membrane-bound organelles.

What is a protozoan trophozoite?

The active, feeding, motile stage of a protozoan.

What is a protozoan cyst?

The dormant, resistant stage that allows survival in harsh environmental conditions.

Which stage is usually responsible for transmission?

The cyst stage.

Which stage is metabolically active?

The trophozoite stage.

What is a pellicle?

A flexible outer covering that helps maintain cell shape while allowing movement.

What is the function of a contractile vacuole?

To remove excess water and maintain osmotic balance.

What is the function of a food vacuole?

To digest ingested food particles.

What are the major forms of asexual reproduction in protozoa?

Binary fission, budding, and schizogony.

What is binary fission?

Asexual reproduction in which one cell divides into two identical daughter cells.

What is schizogony?

A form of asexual reproduction in which the nucleus divides multiple times before the cell splits into many daughter cells.

What are the major forms of sexual reproduction in protozoa?

Conjugation and gamete formation.

What is conjugation?

The exchange of genetic material between two protozoan cells.

Which protozoan phylum includes Paramecium?

Ciliophora.

How does Paramecium move?

Using cilia.

How does Paramecium reproduce asexually?

By binary fission.

How does Paramecium reproduce sexually?

By conjugation.

What characteristic feature identifies Paramecium under the microscope?

It is covered with cilia and has an elongated slipper-shaped body.

Which protozoan causes giardiasis?

Giardia lamblia.

What are the two stages of Giardia?

Trophozoite and cyst.

How can Giardia trophozoites be recognized?

They are pear-shaped with two nuclei that resemble "eyes" and multiple flagella.

How is Giardia transmitted?

By ingestion of cysts in contaminated food or water.

Which protozoan causes trichomoniasis?

Trichomonas vaginalis.

Does Trichomonas vaginalis form cysts?

No, it exists only as a trophozoite.

How does Trichomonas vaginalis move?

Using flagella and an undulating membrane.

How is Trichomonas vaginalis transmitted?

Primarily through sexual contact.

Which protozoan moves using pseudopodia?

Amoeba proteus.

What are pseudopodia?

Temporary cytoplasmic extensions used for movement and feeding.

Which pathogenic amoeba was discussed in lab?

Entamoeba histolytica.

What disease is caused by Entamoeba histolytica?

Amebic dysentery (amoebiasis).

Which stage of Entamoeba histolytica causes tissue damage?

The trophozoite.

Which stage of Entamoeba histolytica is infectious?

The cyst.

Which protozoan phylum includes Plasmodium?

Apicomplexa.

Which disease is caused by Plasmodium vivax?

Malaria.

What organism transmits Plasmodium vivax?

The female Anopheles mosquito.

Which host is the definitive host for Plasmodium?

The mosquito because sexual reproduction occurs there.

Which host is the intermediate host for Plasmodium?

Humans because asexual reproduction occurs there.

What stage is injected into humans by the mosquito?

Sporozoites.

Where do sporozoites first travel in the human body?

The liver.

What process occurs in the liver during malaria infection?

Schizogony producing merozoites.

What cells do merozoites infect after leaving the liver?

Red blood cells.

What causes the periodic fever associated with malaria?

Rupture of infected red blood cells releasing merozoites.

What are gametocytes?

The sexual forms of Plasmodium taken up by the mosquito.

Where does fertilization occur in the malaria life cycle?

In the digestive tract of the mosquito.

Which protozoan is the only ciliated parasite of humans?

Balantidium coli.

How does Balantidium coli move?

Using cilia.

Which free-living flagellated organism was observed in lab but is also discussed with algae?

Euglena.

How does Euglena move?

Using a flagellum.

What unique characteristic does Euglena possess?

It contains chloroplasts and can photosynthesize.

Which protozoan causes African sleeping sickness?

Trypanosoma brucei gambiense.

Which insect transmits Trypanosoma brucei gambiense?

The tsetse fly.

Which structure is commonly used to identify flagellated protozoa?

Flagella.

Which structure identifies amoebas?

Pseudopodia.

Which structure identifies ciliates?

Cilia.

Which protozoa produce both trophozoites and cysts?

Giardia lamblia and Entamoeba histolytica.

Which protozoan does NOT produce a cyst stage?

Trichomonas vaginalis.

Which protozoan reproduces by conjugation?

Paramecium.

Which protozoan reproduces by schizogony in human liver cells?

Plasmodium vivax.

What is the primary function of cyst formation?

Protection and transmission under unfavorable environmental conditions.

How can you distinguish Giardia from Trichomonas microscopically?

Giardia has two nuclei and forms cysts, while Trichomonas has an undulating membrane and does not form cysts.

How can you distinguish Amoeba proteus from Paramecium?

Amoeba moves with pseudopodia and constantly changes shape, while Paramecium is covered in cilia and has a fixed slipper shape.