Maize, Zea mays, is an annual grass in the family Poaceae and is a staple food crop grown all over the world. The maize plant possesses a simple stem of nodes and internodes. A pair of large leaves extend off of each internode and the leaves total 821 per plant. The leaves are linear or lanceolate (lance-like) with an obvious midrib (primary vein) and can grow from 30 to 100 cm (11.839.4 in) in length. The male and female inflorescences (flower bearing region of the plant) are positioned separately on the plant. The male inflorescence is known as the 'tassel' while the female inflorescence is the 'ear'. The ear of the maize is a modified spike and there may be 13 per plant. The maize grains, or 'kernels', are encased in husks and total 301000 per ear. The kernels can be white, yellow, red, purple or black. Maize is an annual plant, surviving for only one growing season and can reach 23 m (710 ft) in height. Maize may also be referred to as corn or Indian corn and is believed to originate from Mexico and Central America.