how is the the third mentioned vegetable in your answer described?
It is tall, hairless bright green unlobed leaves that may be mistaken for docks ("Rumex").
Horseradish
Horseradish grows up to tall, with hairless bright green unlobed leaves up to long that may be mistaken for docks ("Rumex").
when did radishes become a food source for humans They were domesticated in Asia prior to Roman times. how are they consumed? They are mostly eaten raw as a crunchy salad vegetable with bite. are there other varieties? Yes, they differ based on the  seasons when they are grown and a variety of shapes, lengths, colors, and sizes, such as red, pink, white, gray-black, or yellow radishes, with round or elongated roots that can grow longer than a parsnip. what are parsnips? It is a root vegetable closely related to carrot and parsley; all belong to the family Apiaceae. what chemical compound give the first mentioned root vegetable its sharp taste? Glucosinolate, myrosinase, and isothiocyanate is the first mentioned compound found in any other plants? Yes, in mustard, cabbage, and horseradish. is the vegetable mentioned in the beginning and the third mentioned vegetable in the answer above are the same? No, but belongs to the same family of Brassicaceae where are they commonly cultivated and used? It is perennial in hardiness zones 2–9.
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Horseradish [SEP] Description
Horseradish grows up to tall, with hairless bright green unlobed leaves up to long that may be mistaken for docks ("Rumex"). It is cultivated primarily for its large, white, tapered root. The white four-petalled flowers are scented and are borne in dense panicles. Established plants may form extensive patches and may become invasive unless carefully managed. Intact horseradish root has little aroma. When cut or grated, enzymes from within the plant cells digest sinigrin (a glucosinolate) to produce allyl isothiocyanate (mustard oil), which irritates the mucous membranes of the sinuses and eyes. Once exposed to air or heat, horseradish loses its pungency, darkens in color, and develops a bitter flavor.