❖ Mention the name of the skeleton found in Protista. Briefly
describe the structure of skeleton found in Protista
(protozoa) with labeled diagram
skeletal structure , in a broad sense are present in most of Protista. Not
all Protista have skeleton. Many protists secret tectin r mucus like
substance which temporarily serves for protection and anchorage.
However, the majority of them secret permanent shells, consisting of
either organic material, such as gelatin, cellulose and tectin
(pseudochhitin), or an organic matrix containing materials like silica and
calcium carbonate or foreign bodies such as sand particles, etc.
some skeleton found in protistan are mentioned below:
1)Theca
2)Lorica, house or envelope
3)Test or shell
4)walls of cyst and spores
5) internal skeleton
1)Theca:
In formatting a hard shell or test, the first step is to format a theca. The
typical armored dinoflagellates such as Ceratium, Peridium is a close
fitting hardened armour or cuirass, composed of stout cellulose platelets.
, structure: The theca may be composed of a single layer or several
layers .It may be composed either of two valves or of several plates
cemented together. It may be somewhat flexible or rigid due to
impregnation with inorganic salts. Its surface may be plain or variously
sculptures or ornamented, in different species.
Fig: Gonyaulax
2) Lorica, house or envelope: A lorica is a wide fitting wide mouthed house
or envelop usually having the shape of a cup, vase, bell, simple or branching
tube or beaker. The contained organism can protrude out its appendages or the
anterior part of the body through the wide opening of the lorica.
In solitary species, lorica may or may not be stalked. In colonial types, one
lorica may be attached to another directly.
Structure: In ciliophora, lorica is made entirely of tectin or may also include
diatom shells, sand grains and foreign particles. In stenton, It is composed of
gelatinous secretion reinforced with foreign material. In heliozoa, the body
describe the structure of skeleton found in Protista
(protozoa) with labeled diagram
skeletal structure , in a broad sense are present in most of Protista. Not
all Protista have skeleton. Many protists secret tectin r mucus like
substance which temporarily serves for protection and anchorage.
However, the majority of them secret permanent shells, consisting of
either organic material, such as gelatin, cellulose and tectin
(pseudochhitin), or an organic matrix containing materials like silica and
calcium carbonate or foreign bodies such as sand particles, etc.
some skeleton found in protistan are mentioned below:
1)Theca
2)Lorica, house or envelope
3)Test or shell
4)walls of cyst and spores
5) internal skeleton
1)Theca:
In formatting a hard shell or test, the first step is to format a theca. The
typical armored dinoflagellates such as Ceratium, Peridium is a close
fitting hardened armour or cuirass, composed of stout cellulose platelets.
, structure: The theca may be composed of a single layer or several
layers .It may be composed either of two valves or of several plates
cemented together. It may be somewhat flexible or rigid due to
impregnation with inorganic salts. Its surface may be plain or variously
sculptures or ornamented, in different species.
Fig: Gonyaulax
2) Lorica, house or envelope: A lorica is a wide fitting wide mouthed house
or envelop usually having the shape of a cup, vase, bell, simple or branching
tube or beaker. The contained organism can protrude out its appendages or the
anterior part of the body through the wide opening of the lorica.
In solitary species, lorica may or may not be stalked. In colonial types, one
lorica may be attached to another directly.
Structure: In ciliophora, lorica is made entirely of tectin or may also include
diatom shells, sand grains and foreign particles. In stenton, It is composed of
gelatinous secretion reinforced with foreign material. In heliozoa, the body
