Dermatogen is a tissue formed by apical meristem and gives rise to
$T.S.$ of stem of Cucurbita can be identified from the $T.S.$ of sunflower stem by the presence of
Amphivasal or leptocentric vascular bundles are found in
A nail is driven into the trunk of a $30$ year old tree at a point $1$ meter above the soil level. The tree grows in height at the rate of $0.5$ meters a year. After three years, the nail will be