Based on which of the following characteristics has the above grouping been done?
(a) Living or non-living
(b) Presence or absence of legs
(c) Useful or harmful animals
(d) Presence or absence of backbone
In both the groups there are organisms without backbone, then how will (d) be the correct option ???
Ans 1: (Master Answer)
Group P: Sponges, corals, worms, insects, spiders and crabs are all sub-groups of the invertebrate group - they do not have a backbone. Group Q: Fish, reptiles, birds, amphibians and mammals are different sub-groups of vertebrates - they all have internal skeletons and backbones. Hence d is the correct option.