The reptiles,like dinosaurs,were dominant in the . . . . . . period.

Match the following columns:

Column-$I$ (Organism)	Column-$II$ (Origin)
$P$. Invertebrates	$I$. $500$ million years ago
$Q$. Jawless fish	$II$. $350$ million years ago
$R$. Sea weeds and few plants	$III$. $320$ million years ago

The origin of seeds in land plants was achieved about $345 \; \text{million}$ years ago, in lineages recognized as ancestral to all more advanced vascular plants in:

The first mammals appeared in which geological period?

The earliest reptiles evolved in which geological period?

In which period did giant reptiles dominate the earth?