zoo-, zoa-, zo-, -zoic, -zoid, -zoite, -zoal, -zonal, -zooid, -zoon, -zoa, -zoan

Free-swimming larva of certain crustaceans: The larvae of the spiny lobster and the sea-crayfish are called phyllozooids.

An obsolete term for minute water colonial invertebrates; bryozoan: Polyzoans are animals that form branching, mosslike colonies, and reproduce by budding.

A reference to marine animals that form colonies of zooids: In Jane's biology book she read about polyzoan lifeforms that grouped together as the moss-animalcules, sea mosses, or sea-mats do.

Concerning an organism composed of various zooids: A polyzoic lifeform has many motile cells or bodies, like a tapeworm, that typically divide into proglottids that consistently shed into the surrounding area to infect other animals.

The older Paleozoic faunal epoch, the age of primitive invertebrates: The Proterozoic marks the beginning of the Phanerozoic, between the Archean Eon and the Cambrian period, where rocks accumulated, oxygen buildup took place, and early forms of soft-footed animals came into being.

Formerly, the name of an animal phylum comprising a large, diverse assortment of microscopic or near-microscopic one-celled heterotrophic organisms: The Protozoa is the subkingdom which comprises all unicellular animals (by some regarded as non-cellular).

Included in the group are some which may also be classified as plants, the distinction being that these possess chlorophyll.

That which destroys protozoa or protozoans: Jacky learned that a special agent called protozoacide used to be used to kill or exterminate tiny unicellular organisms.

A one-celled microscopic animal included in the kingdom of Protista: A protozoan can be a flagellate, ciliate, sporozoan or amoeba.

A protozoan can be any of a diverse group of eukaryotes (organisms composed of one or more cells, each of which contains a clearly defined nucleus enclosed by a membrane, along with organelles [small, self-contained, cellular parts that perform specific functions]), of the kingdom Protista, that are primarily unicellular, existing singly or aggregating in colonies, are usually nonphotosynthetic, and are often classified further into phyla according to their capacity for and means of motility, as by pseudopods, flagella, or cilia.

1. In zoology, pertaining to the Protozoa: Protozoic creatures are one-cells eukaryotes and can be parasitic, which feed on organic substances like organic debris or tissues, or they can be free-living.
2. In geology, referring to the remains of the earliest discovered life of the globe: Protozoic organisms included the mollusks, radiates, and protozoans.

"Radiates" are fibers of the articular capsule (sac enclosing a joint) that radiate from the costal cartilages to the anterior surface of the sternum.

The branch of zoology dealing with the study of protozoa: Protozoology is the area of research that focuses on single-celled parasitic organisms with flexible membranes and the ability to move.

A unicellular or non-cellular animal organism: The protozoon, or protozoan, is one of the primitive forms of animal life, and being a protist or eukaryote, is not a fungus, plant or animal, and it feeds by the way of heterotrophy.

A phagocyte that consumes protozoa: The protozoophages are specialized cells in the immune system that ingest and usually destroy foreign particulate matter or microorganisms, like viruses, bacteria, and waste.

In biology, concerning the pollination by protozoa: The action of protozoophilous single-celled microscopic animals, besides protozoa, can be seen with regard to some aquatic plants.

This word applies to a term called "malariotherapy" which was used between 1917-1950 for the treatment of syphilis.

In 1917, Julius Wagner von Jauregg (Austrian psychiatrist and neurologist) began inoculating paretics (psychosis associated with neurosyphilis) with blood from patients with benign tertian malaria caused by Plasmodium vivax (protozoan parasite that causes vivax malaria). The elevated temperature of the body caused by the malaria parasite killed the temperature sensitive "Treponema pallidum" (a microscopic bacterial organism that causes syphilis).

Institutions for malariotherapy rapidly spread throughout Europe and the technique was also adopted in several centers in the United States. In this way, thousands of syphilitics were saved from a sure and agonizing death.

Pertaining to the later geological Quaternary period, the era of man: The psychozoic age of time designates the beginning of the existence of humans and their intelligence, and of other living creatures.