Editing Cartilage (section)

====Mollusks====
In cephalopods, the models used for the studies of cartilage are ''[[Octopus vulgaris]]'' and ''[[Sepia officinalis]]''. The cephalopod cranial cartilage is the invertebrate cartilage that shows more resemblance to the vertebrate hyaline cartilage. The growth is thought to take place throughout the movement of cells from the periphery to the center. The chondrocytes present different morphologies related to their position in the tissue.<ref name="ColeHall2004" />
The embryos of ''S.&nbsp;officinalis'' express ColAa, ColAb, and hyaluronan in the cranial cartilages and other regions of chondrogenesis. This implies that the cartilage is fibrillar-collagen-based. The ''S.&nbsp;officinalis'' embryo expresses hh, whose presence causes ColAa and ColAb expression and is also able to maintain proliferating cells undiferentiated. It has been observed that this species presents the expression SoxD and SoxE, analogs of the vertebrate Sox5/6 and Sox9, in the developing cartilage. The cartilage growth pattern is the same as in vertebrate cartilage.<ref name="TarazonaEtAl2016" />

In gastropods, the interest lies in the [[odontophore]], a cartilaginous structure that supports the radula. The most studied species regarding this particular tissue is ''[[Busycotypus canaliculatus]]''. The odontophore is a vesicular cell rich cartilage, consisting of vacuolated cells containing myoglobin, surrounded by a low amount of extra cellular matrix containing collagen. The odontophore contains muscle cells along with the chondrocytes in the case of ''[[Lymnaea]]'' and other mollusks that graze vegetation.<ref name="ColeHall2004" />