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

Give the differences between bony and cartilaginous fish.

Meena and Hari observed an animal in their garden. Hari called it an insect while Meena said it was an earthworm. Choose the character from the following which confirms that it is an insect.

Charles Darwin first described the idea of evolution in his book "The Origin of Species". Define the concept of evolution.

Organisms without a nucleus and cell organelles belong to:
$(i)$ Fungi
$(ii)$ Protista
$(iii)$ Cyanobacteria
$(iv)$ Archaebacteria

State appropriate terms for the following:
$(i)$ Amphibians of the plant kingdom.
$(ii)$ Plants not having well-differentiated body design.
$(iii)$ Single-celled,eukaryotic,and photosynthetic organism.