Protozoa

Protozoa

1) Ectoplasm and endoplasm

One of the unique features of protozoa is the presence of ectoplasm and endoplasm. Ectoplasm is the gelatinous cytoplasm right under plasma membrane while endoplasm is surrounded by ectoplasm. The fluid which most organelles located.

2) Pellicle

 

In addition, protozoa has pellicle which is the thin layer supporting the cell membrane. It is embedded in ectoplasm.



3) 2 types of nucleus.

Protozoa has macronucleus and micronucleus. The larger nucleus, macronucleus performs normal cell functions like respiration, protein synthesis and digestion while the smaller micronucleus is responsible for cell division and used only during reproduction.

 

Characteristic	Micronucleus	Maconucleus
Polidy	2n	~1000n
Genome size	100-120 megabases	80-90% micronuclear complexity
Number of chromosomes	~50	~350
Chromosome size	~2 megabases	~300(50-1000) kilobases

 

 

4) Vacuoles

 







 

Contractile vacuole is for osmoregulatory. In other words it controls the amount of water enter and leaving the cell to prevent bursting of cell.



 

5) Chemoheterotrophic

 

Protozoa can either be holozoic nutrition or saprozoic nutrition. Holozoic nutrition is the intake of solid nutrients through phagocytosis while saprozoic nutrition is the intake of soluble nutrients through pinocytosis.

 

Moreover, there are three types of locomotory organelles for protozoa. The first one will be pseudopodia, the false foot in amoeba. Next is flagella and cilia.

 

Asexual reproduction in protozoa is binary fission while sexual reproduction is conjugation.

 

Protozoa classifies according to

I. Type of nuclei II. Mode of reproduction III. Mechanism of locomotion

 

For instance, Phylum Sarcomastigophora has only single type of nucleus. Subphylum Mastigophora has flagella while subphylum Sarcodina has pseudopodia.

 

Subphylum Mastigophora has two types. Phytoflagellates with the presence of chlorophyll while zooflagellates without the presence of chlorophyll.

 

Besides, apicomplexa has it's unique feature which is apical complex.

 

Lastly, Phylum Ciliophora is the largest phylum in protozoa. It is unicellular and has cilia as its locomotory organelle. It has two macronucleus and micronucleus.