Question

The trout, duck, crocodile, water vole and frog are all called chordates because they have a what?

Answer 1

Explanation:

Amphioxus, frog, sea Horse and crocodile are belong to the group of chordates. Chordates are characterised by three primary chordate features- the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits. These animals have the pharyngeal gills slits which helps to draw water. These organs act as filter feeding organs and are most commonly found in invertebrate chordates like tunicates and lancelets.

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