In biology, a lorica is a shell-like protective outer covering, often reinforced with sand grains and other particles that some
protozoan
Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histo ...
s and
loriciferan
Loricifera (from Latin, '' lorica'', corselet (armour) + ''ferre'', to bear) is a phylum of very small to microscopic marine cycloneuralian sediment-dwelling animals that had been determined to be 37 described species, in 9 genera, bu ...
animal
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage ...
s secrete. Usually it is tubular or conical in shape, with a loose case that is closed at one end. An example is the protozoan genus ''
Stentor
In Greek mythology, Stentor (Ancient Greek: Στέντωρ; ''gen''.: Στέντορος) was a herald of the Greek forces during the Trojan War.
Mythology
Stentor is mentioned briefly in Homer's ''Iliad'' in which Hera in the guise of Stent ...
'', in which the lorica is trumpet-shaped. In the
tintinnids, the lorica is frequently transparent and is used as
domicile. ''
Halofolliculina corallasia'' has a lorica that is attached as an outer structure, and into which it retracts when disturbed.
There are three phases in the formation of lorica: agglomeration in a natural
cast
Cast may refer to:
Music
* Cast (band), an English alternative rock band
* Cast (Mexican band), a progressive Mexican rock band
* The Cast, a Scottish musical duo: Mairi Campbell and Dave Francis
* ''Cast'', a 2012 album by Trespassers William
...
; helical extension; and stabilization.
[
]
The original meaning of the word is: cuirass, a type of chest armor, originally made of leather, afterward of plates of metal or horn sewed on linen or the like.
See also
*
Chitin
Chitin ( C8 H13 O5 N)n ( ) is a long-chain polymer of ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is probably the second most abundant polysaccharide in nature (behind only cellulose); an estimated 1 billion tons of chit ...
*
Periostracum
The periostracum ( ) is a thin, organic coating (or "skin") that is the outermost layer of the shell of many shelled animals, including molluscs and brachiopods. Among molluscs, it is primarily seen in snails and clams, i.e. in gastropods ...
*
Tectin
Notes
Ciliate biology
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