কর্ডাটা: সংশোধিত সংস্করণের মধ্যে পার্থক্য
বিষয়বস্তু বিয়োগ হয়েছে বিষয়বস্তু যোগ হয়েছে
৪০ নং লাইন:
{{Annotation|200|305|19 {{=}} [[হেপাটিক সিকাম]] ([[যকৃৎ]]-সদৃশ অঙ্গ) }}
}}
কর্ডাটারা form a [[phylum]] of creatures that are based on a bilateral [[body plan]]<ref>{{
| last = Valentine | first = J.W. | year = 2004 | title = On the Origin of Phyla
| publisher = University Of Chicago Press | location = Chicago | isbn = 0226845486
| page=7
}}"<cite>Classifications of organisms in hierarchical systems were in use by the seventeenth and eighteenth centuries. Usually organisms were grouped according to their morphological similarities as perceived by those early workers, and those groups were then grouped according to ''' their''' similarities, and so on, to form a hierarchy.</cite>"
</ref>, and is defined by having at some stage in their lives all of the following:<ref name="RychelSmithShimamotoSwalla2006">{{
| author=Rychel, A.L., Smith, S.E., Shimamoto, H.T., and Swalla, B.J. | year=2006
| title=Evolution and Development of the Chordates: Collagen and Pharyngeal Cartilage
৫৬ নং লাইন:
* [[Pharyngeal slit]]s. The [[pharynx]] is the part of the [[throat]] immediately behind the mouth. In [[fish]] the slits are modified to form [[gills]], but in some other chordates they are part of a [[filter feeding|filter-feeding]] system that extracts particles of food from the water in which the animals live.
* A muscular tail that extends backwards behind the [[anus]].
* An [[endostyle]]. This is a groove in the [[Anatomical terms of location#Dorsal and ventral|ventral]] wall of the pharynx. In [[filter feeding|filter-feeding]] species it produces [[mucus]] to gather food particles, which helps in transporting food to the [[esophagus]].<ref name="Ruppert2005">{{
| author=Ruppert, E. | journal=Canadian Journal of Zoology | volume=83 | pages=8–23 | year=2005
| doi = 10.1139/Z04-158
| |||