Question

Fill in the blanks:

The connecting link between invertebrates and chordates is the (i)______ that belongs to the phylum (ii)_______ and has a larval form called (iii)_______ which resembles the larval form of (iv)_________.

• A. Acorn worm --- Hemichordata --- Tornaria
• B. Acorn worm --- Hemichordata --- Trochophore.
• C. Acornis worm --- Hemichordata --- Tornaria.
• D. None of these

Answer 1

The correct option is C

Acornis worm --- Hemichordata --- Tornaria.

Acorn worm (Balanoglossus), belonging to the Phylum Hemichordata, is said to be the connecting link between the non-chordates and chordates. This is because it possesses certain characters found in chordates, in addition to many of its invertebrate features. The larval form of hemichordates is called tornaria, which resembles the bipinnaria larva of echinoderms.