When leaves bear flowers or inflorescences in their axils,they are called:

Sunken stomata are usually found in the leaves of

What is a leaf called that has stomata only on its upper surface?

In $Acacia$ species,the first few leaves are pinnately compound. Then there are leaves with flattened petiole and fewer pinnae. The leaves of the adult plant have parallel-veined flattened petioles and no pinnae. It shows that:

Identify the plant that shows the heterophylly depicted in the image below.

$A$: In $Smilax$,stipules change into tendrils and help in climbing.
$R$: Parallel venation is found in this plant.