NEET BIOLOGY

Detailed explanation-1: -In chordates, four common features appear at some point during development: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail. The dorsal hollow nerve cord derives from ectoderm that rolls into a hollow tube during development. In chordates, it is located dorsal to the notochord.

Detailed explanation-2: -Animals in the phylum Chordata share four key features: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

Detailed explanation-3: -The characteristic features of Chordata are a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.

Detailed explanation-4: -It is a hollow tube of nervous tissue. It constitutes the central nervous system of chordates & develops into the spinal cord and brain in vertebrates. In chordates, the dorsal nerve cord is present in the embryonic stage. This develops in the brain and spinal cord.

Detailed explanation-5: -So, the correct answer is ‘Solid’.