The main stalk of a plant is called the stem. It provides support for the plant and serves as a conduit for nutrients and water between the roots and leaves.
An ovary is the part of the plant an apple comes from.
Banana is the fruit of a plant
A beet is a root plant.
Parsnips come from the root of the parsnip plant. They are a biennial plant, and the edible part is the thick, white taproot that grows beneath the ground.
It is a plant in it's own right, not part of anything else.
kiwi comes from the bud of the plant
Caraway is the seed of the caraway plant.
stem
Root.
the flower
stems