General characters of Phylum Protozoa

General characters of Phylum Protozoa:

They are parasites or free-living.

• They have flagella for locomotion.
• Their body is covered by a cuticle or pellicle.
• Freshwater forms have a contractile vacuole.
• These are acellular organisms with Protoplasmic organisation.
• Division of labour is at the level of cell organelles.
• These undergo asexual reproduction either by binary fission or by multiple fission.
• Some undergo sexual reproduction by conjugation or autogamy or endomixis.
• All fresh water and many parasitic Protozoans undergo encystment for dispersal and perennation.
• Nutrition is either holozoic or saprozoic or parasitic.