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

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.

State whether the following statement is true or false:
Cryptogamae means those with open reproductive organs.

Which among the following have scales?
$(i)$ Amphibians
$(ii)$ Pisces
$(iii)$ Reptiles
$(iv)$ Mammals

Hard calcium carbonate structures are used as a skeleton by

Associate the following features with appropriate organisms and their kingdom [in $(ii)$ and $(iv)$],division [in $(i)$] and phylum [in $(iii)$ and $(v)$].
$(i)$ Presence of pyrenoids
$(ii)$ Presence of heterocysts
$(iii)$ Presence of genital papillae and anus
$(iv)$ Presence of chloroplast and flagella
$(v)$ Presence of palp and parapodia