Miller and Urey performed an experiment to prove the origin of life. They took gases $N H_{3} \wedge H_{2}$ along with
$N _{2}$ and $H _{2} O$
$H _{2} O$ and $CH _{4}$
$CH _{4}$ and $N _{2}$
$CO _{2}$ and $NH _{3}$
Connecting links are organism which shows characters of
An important evidence in favour of organic evolution is the occurrence of
A species that contains two or more sub-species are called