Proboscis gland is a/an

Which organ is responsible for excretion in animals belonging to the phylum Hemichordata?

Members of $Hemichordata$ are

Write a short note on Hemichordata.

The phylum which was earlier considered as a sub-phylum under $Chordata$ but now placed as a separate phylum in non-chordates is:

Which of the following organisms exhibits bilateral symmetry?