Difference between revisions of "Organic lining"

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(Definition)
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*''according to Hottinger (2006):''
 
*''according to Hottinger (2006):''
  
'''ORGANIC LINING''' - an organic cell envelope said to consist of mucopolysaccharides, located between the plasmalemma and the biomineralized cell envelope. It covers the protoplasmic cell body in the chamber lumina and the connecting cavities inbetween them (foramina, stolons), but never the interlocular spaces. Whether it occurs in chamberlet cavities of the [[supplemental skeleton]] is unknown at present. May be discontinuous or extremly thin over pore mouths and/or in the ultimate and penultimate chambers, and commonly thickens in the direction of earlier growth stages. May be involved in stolon plugging. May be resorbed together with the biomineralized wall when brood chambers are formed. The organic lining resists dissolution of the biomineralized shell by acidic attack, maintains the shape of the protoplasmic body and is capable of remineralizing its shell when the ambient environment returns to normal. However, the role of the organic lining in biomineralization has to be investigated further.  
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'''ORGANIC LINING''' - an organic cell envelope said to consist of mucopolysaccharides, located between the plasmalemma and the biomineralized cell envelope. It covers the protoplasmic cell body in the chamber lumina and the connecting cavities inbetween them (foramina, stolons), but never the [[interlocular space]]s. Whether it occurs in chamberlet cavities of the [[supplemental skeleton]] is unknown at present. May be discontinuous or extremly thin over pore mouths and/or in the ultimate and penultimate chambers, and commonly thickens in the direction of earlier growth stages. May be involved in stolon plugging. May be resorbed together with the biomineralized wall when brood chambers are formed. The organic lining resists dissolution of the biomineralized shell by acidic attack, maintains the shape of the protoplasmic body and is capable of remineralizing its shell when the ambient environment returns to normal. However, the role of the organic lining in biomineralization has to be investigated further.  
  
 
''Remarks:'' There is no reason to abandon the traditional designation of organic lining (as used by Loeblich & Tappan, 1987) in favour of "inner organic lining" (IOL) as introduced by Anderson and Bé (1978). The eventual use of an "outer organic layer" called for by the IOL that might be applied either to the outer organic cover of the biomineralized shell or to the temporary organic envelope that in some species protects the process of chamber formation would add confusion in the description of the several layers of the cell envelope and their specific functions. Moreover, the term "inner organic lining" is easily confused with the term "inner lining" which is equivalent to "inner lamella", the inner calcified lamella of the primary wall in perforate foraminifera.
 
''Remarks:'' There is no reason to abandon the traditional designation of organic lining (as used by Loeblich & Tappan, 1987) in favour of "inner organic lining" (IOL) as introduced by Anderson and Bé (1978). The eventual use of an "outer organic layer" called for by the IOL that might be applied either to the outer organic cover of the biomineralized shell or to the temporary organic envelope that in some species protects the process of chamber formation would add confusion in the description of the several layers of the cell envelope and their specific functions. Moreover, the term "inner organic lining" is easily confused with the term "inner lining" which is equivalent to "inner lamella", the inner calcified lamella of the primary wall in perforate foraminifera.

Revision as of 09:54, 31 October 2019