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Ontology Browser

Parent Terms Term With Siblings Child Terms
skeletal tissue +    
amniotic fluid 
blood clot 
bodily fluid +  
bodily gas +  
bone tissue +  
cartilage tissue +  
chondroid tissue 
colloid of thyroid follicle 
dental plaque +  
digestive system secreted substance 
excreta +  
follicular fluid 
ingested food +  
interstitial fluid +  
mesangial matrix 
mineralized skeletal tissue +  
An organic-inorganic composite material produced by some mollusks as an inner shell layer; it is also what makes up pearls. It is very strong, resilient, and iridescent. Nacre is found in some ancient lineages of bivalve gastropod and cephalopod. The inner layer in the great majority of mollusk shells is porcellaneous, not nacreous, frequently resulting in a non-iridescent shine or less commonly in non-nacreous iridescence such as flame structure (e.g. conch pearl). Pearls and the inside layer of pearl oyster and freshwater pearl mussel shells are made of nacre. Many other families of mollusk also have a nacreous inner shell layer, including marine gastropods such as the Haliotidae, the Trochidae and the Turbinidae. Nacre is composed of hexagonal platelets of aragonite (a form of calcium carbonate) 10-20 µm wide and 0.5 µm thick arranged in a continuous parallel lamina. These layers are separated by sheets of organic matrix composed of elastic biopolymers (such as chitin, lustrin and silk-like proteins)[WP].
non-mineralized chondroid tissue +  
ocular refractive media +  
odontoid tissue +  
oronasal secretion 
regurgitated substance +  
reproductive gland secretion +  
respiratory system fluid/secretion +  
ruminal fluid 
secretion of crop 
secretion of exocrine gland +  
semen +  
skin secretion 

Exact Synonyms: mother of pearl
Xrefs: MESH:D060734 ;   Wikipedia:Nacre
Definition Sources: Wikipedia:Nacre

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