The animals having a two-chambered heart belong to the class:

Associate the following features with the groups in which they first appeared:
$(a)$ Vascular tissues
$(b)$ Notochord
$(c)$ Seeds inside fruits

Name the phylum to which Leech and Earthworm belong.

Which of the following is not an Annelid?

Give the appropriate term for each of the following:
$(a)$ Complex sugar that makes the fungal cell wall
$(b)$ Exposed seeds
$(c)$ Blue-green algae
$(d)$ Basic unit of classification
$(e)$ Group of unicellular eukaryotic organisms

Which of the following is not a criterion for classification of living organisms?