Parasitology Exam 2

Unicellular organisms

No matter how complex their bodies may be, all different structures are contained in a single cell

Eukaryotic

They’re DNA is compartmentalized within a nucleus; different from bacteria (which are prokaryotic)

Protozoa locomotion

Flagellum (single) / Flagella (multiple); cilia, pseudopodia

Flagellum (single) / Flagella (multiple)

Whip-like tail for propulsion attached to basal body, may propel and undulating membrane (if present)

Cilia

Fine short hairs, each arising from a basal body that beat in unison

Pseudopodia

Prolongation of cytoplasm

Protozoa get their nutrition by

Endocytosis

Endocytosis

Cell membrane gradually enveloping the droplet or object which has become adherent to its outer surface, particles are carried into the cell and digested by lysosomes, undigested material is extruded from cell

Pinocytosis

Cell drinking; liquids or dissolved substances

Phagocytosis

Cell eating; large particles like bacteria or debris

Protozoa “cell mouth”

Cytostome

Sporozoite

The infective stage of some Protozoa; this is the stage where it enters the host

Trophozoite

Stage of Protozoa while in host; active feeding and growth until protozoan cell division commences

Asexual reproduction steps (most Protozoa)

Binary fission, budding, merogony (schizongony)

Binary fission

One cell splits into 2 identical cells

Budding

Small new cell buds off parent (babesia spp)

Merogony (schizogony)

Trophozoit grows to large size while nucleus divides repeatedly resulting in a meront (schizont). The meront contains many separate organisms called merozoites, their meront eventually ruptures, liberating individual merozoites

Merogony is synonymous with

Schizogony (depends on specific Protozoa)

Meront is synonymous with

Schizont