Who introduced the system of scientific nomenclature of organisms?

In taxonomic hierarchy,family comes between

Plants that do not have well-differentiated body design fall into the group called

Classify the phylum Vertebrata into their further groups by giving two characteristics of each.

Identify the phylum for the following characteristics given:
$(a)$ Organisms with jointed appendages.
$(b)$ Organisms are generally flatworms.
$(c)$ Body is segmented.
$(d)$ Skin of organisms is full of spikes.

Identify the animal and plant groups having:
$(a)$ Animals without tissues,body bearing pores.
$(b)$ Plant body differentiated into roots,stems and leaves but do not produce seeds.
$(c)$ Body dorsoventrally flattened without coelom.
$(d)$ Segmented worms with true body cavity with extensive organ differentiation.