Plant epidermis cellulose cell walls, SEM

Plant epidermis cellulose cell walls from a ragweed (Ambrosia psilostachya) anther, coloured scanning electron micrograph (SEM). Ambrosia psilostachya is known as ragweed, a perennial herb in the family Asteraceae. It is also known as Cuman ragweed, perennial ragweed or western ragweed. Its pollen is allergenic. Ragweed is a main cause of weed allergies. Ragweed pollen is notorious for causing allergic reactions in humans, specifically allergic rhinitis. Up to half of all cases of pollen-related allergic rhinitis in North America are caused by ragweeds. One of the main contributors to fall allergies is the ragweed plant. A single plant can produce one billion pollen grains per season. Ragweed grows abundantly throughout the South, North, and Midwest, and its lightweight pollen grains can travel up to 400 miles in the wind. Magnification: x500 when shortest axis printed at 25 millimetres.