CBSE Class 7 Answered

Onion and garlic both are modified stem known as bulb.

Stem of garlic is modified to remain underground. As a result, the fleshy white portion of garlic are actually the leaves arising from the reduced stem. Thus, garlic is a compound tunicated bulb. It cannot be categorised completely as a stem or a root.

An onion is actually a reduced stem surrounded by very fleshy scale leaves that surround a central bud. The flattened yellow part seen at the flatter base is actually the stem, from which the scale leaves arise on the top and the adventitious fibrous roots arise from the bottom.