State the phylum to which liver fluke and Planaria belong.

Give the main features of chordates.

$X, Y$ and $Z$ are living organisms.
$(a)$ Identify the group to which they belong on the basis of following features:
$(i)$ $X -$ Microscopic,unicellular,prokaryotic.
$(ii)$ $Y -$ Microscopic,unicellular,eukaryotic and shows locomotion with the help of pseudopodia/flagella.
$(iii)$ $Z -$ Multicellular,filamentous,eukaryotic,autotrophic and aquatic.
$(b)$ Which amongst the above is most advanced?
$(c)$ Name one organism each belonging to the groups of $X, Y$ and $Z$.

Which among the following have an open circulatory system?
$(i)$ Arthropoda
$(ii)$ Mollusca
$(iii)$ Annelida
$(iv)$ Coelenterata

Write the names of a few thallophytes. Draw a labelled diagram of Spirogyra.

Which of the following is not an Annelid?