Parasit protozoa

Ectoplasm

- transparent, less granular and more homogenous

- movement, respiration, procurement of food, discharge of metabolic wastes and

protection

Pseudopodia

temporary extensions of ectoplasm

Flagella

long, slender, whiplike structures

Cilia

similar to flagella but shorter

Undulating membrane

fin-like extension along the outer edge of the body

Cytostome

cell mouth

Cytopyge

cell anus

Cyst wall

protection and survival

Endoplasm

- moderately dense granular protoplasm

- metabolism and nutrition, storage of food

Mitochondria, Golgi apparatus, Endoplasmic reticulum, Contractile vacuoles, Glycogen vacuole, Chromatoidal bodies

Organelles/structures found in endoplasm include:

NUCLEUS

Contains chromosome and is bounded externally by a nuclear membrane

Vesicular nucleus, Compact nucleus

Two Types of Nucleus among Protozoa

Vesicular nucleus

- large, membrane-bound nucleus with abundant nucleoplasm and sparse

chromatin, often containing a central mass of aggregated dense chromatin called

karyosome (endosome)

Compact nucleus

More compact, darker in color, and densely packed, with a solid mass of

chromatin

TROPHOZOITE

• Active and reproductive stage

• Cannot survive outside the host

• Motile stage

• Pathogenic stage

• Formed through excystation

CYST

• Active and reproductive stage

• Cannot survive outside the host

• Motile stage

• Pathogenic stage

• Formed through excystation

Encystation

– from active trophozoite into inactive cyst stage

Excystation

from inactive cyst stage to active trophozoite

Binary fission

- A single organism divides into two genetically identical daughter cells

- Amoebas (random), Flagellates (longitudinal), Ciliates (transverse)

Multiple fission

- a single parent cell divides to produce many daughter cells

- Example is schizogony (schizonts or meronts produce merozoites which will undergo

merogony)

Syngamy

- fusion of two gametes (microgamete and macrogamete) to form a zygote during the sexual phase of a parasite’s life cycle

Conjugation

- Two compatible protozoan cells temporarily unite together to exchange genetic material, but no new organism is immediately formed