The stem develops from which part of the embryo?

Which of the following is an enlarged,vertically growing,spherical underground stem?

In $Amorphophallus$ and $Colocasia$ $(Araceae)$, an extremely enlarged underground vertical stem meant for vegetative reproduction and storage is:

Turmeric powder is obtained from which part of the plant?

What is a stem? Describe the parts of the stem and its normal functions.

Thorn of Bougainvillea is modified: