Protista : A kingdom which includes all unicellular organisms lacking a definite cellular arrangement.

Pellicle : A thin flexible proteinic membrane around certain protozoans.

Diatom :
A common name for algae composed of unicellular, microscopic organisms occurring on water surfaces and certain brown pigment in addition to chlorophyll.

Dinoflagellate :
Group of unicellular algae with cellulose wall divided into plates which give them an armoured appearance.

Paramylum :
An insoluble carbohydrate similar to starth stored as food reserve.

Cysts :
The spore like structure formed in many protists to overcome adverse condition.

Syngamy :
Process of fusion of two haploid cells is termed syngamy.

Gametical meiosis :
When meiosis occurs in diploid individuals to produce haploid gametes.

Zygotic meiosis :
When meiosis occurs in the zygote immediately after its formation to produce haploid individuals.

Diatomaceous Earth :
These are cell wall deposits left behind in large amount by diatoms.

Pseudoplasmodium :
 An aggregation of numerous amoeboid cells. These are not fused with each other and moving together like a mass of protoplasm.

Plasmodium :
An acellular mass of multinucleated protoplasm which slowly streams or glides over decaying leaves or logs.

Protozoa :
(heterotrophic) A phylum or sub-kingdom of protista includes all the acellular or unicellular organisms. These feed as holophytes. About 3000 described
species are further divided into four classes :
  1. Aliophera,
  2. Sporozoa,
  3. Rhizopoda,
  4. Mastigopora
Algae : A phylum of protista, chlorophyll bearing sea weed, covering about 25,000 described species in the following classes
  1. Bacillariophyta – Diatom
  2. Charophyta – Stonewarts
  3. Cholerophyta – Green algae
  4. Chrysophyta – Golalem brown algae.
Cryptophyta : Hidden algae (producing buds underground or underwater)
                Euglenophyta – Euglenoids
                Phaeophyta – Brown algae
                Pyrrophyta – Fire algae
                Rhodophyta – Red algae
                Xanthophyta – Yellow green algae

Auropodium :
It is a pseudonium containing straight, rigid axoneme.

Cilia :
Microscopic motile threads projecting from certain cell surface which stroke rhythmically together like oars.

Diatom :
They have a pill box shape. They reproduce asexually by fission producing successive smaller generations until size is restored through sexual reproduction by auxospores.

Flagella :
A microscopic motile thread projecting from certain cell surfaces and causing movement by lashing back and forth. They are usually larger than cilia.

Nuclear dimorphism :
A protest is said to show nuclear dimorphism if it contains two morphologically and functionally distinct nuclei i.e. small micronucleus and large macronucleus.

Psuedopodia :
It is a temporary finger like projection that helps in locomotion and feeding.

Slime mold :
They are multinucleate, they lack cell walls, they display amoeboid movements.

Syngamy :
It is the process of fusion of haploid gametes during sexual reproduction. It is followed by the meiosis process.

Diatomaceous earth :
Diatoms contains cells walls of cellulose and impregnated with silica. Such cell walls of diatoms are indestructible and are left behind in large amount of fossils cell wall deposits. These are known as Diatomaceous Earth.

Cysts :
Under unfavourable conditions, some protists form hard and thick covering around the protoplasm of cell. This tough covering is cysts.