Kids Research Express

Rice, plant that produces an edible grain; the name is also used for the grain itself. Rice is the primary food for half the people in the world. In many regions it is eaten with every meal and provides more calories than any other single food. A kernel or grain of rice is a seed that contains an embryonic rice plant. The hull, a hard protective covering, surrounds the bran, which consists of layers of fibrous tissue that contain protein, vitamins, minerals, and oil. Beneath the bran is the endosperm, which makes up most of the rice grain. The endosperm contains starch, the energy source used by the germinating seed. The bran and endosperm are the edible portions of the grain. A rice plant, a type of grass , has narrow, tapered leaves and grows from about 60 to 180 cm (about 2 to 6 ft) tall. Several flower stalks emerge from the plant, and in most varieties, a loose cluster of branching stems, called a panicle, radiates from the top of each stalk with small green flowers hanging from e...

Corn or Maize, common name for the cereal grass widely grown for food and livestock fodder. Corn ranks with wheat and rice as one of the world’s chief grain crops. The corn plant has an erect, solid stem, rather than the hollow one of most other grasses. It varies widely in height, some dwarf varieties being little more than 60 cm (2 ft) at maturity, whereas other types may reach heights of 6 m (20 ft) or more. The average is 2.4 m (8 ft). The leaves, which grow alternately, are long and narrow. The main stalk terminates in a staminate (male) inflorescence, or tassel. The tassel is made up of many small flowers termed spikelets, and each spikelet bears three small anthers, which produce the pollen grains, or male gametes. The pistillate (female) inflorescence or ear is a unique structure with up to 1,000 seeds borne on a hard core called the cob. The ear is enclosed in modified leaves called husks. The individual silk fibers that protrude from the tip of the ear are the elongated style...

Wheat, common name for cereal grasses of a genus of the grass family, cultivated for food since prehistoric times by the peoples of the temperate zones and now the most important grain crop of those regions (see Agriculture ). Wheat is a tall, annual plant attaining an average height of 1.2 m (4 ft). The leaves, which resemble those of other grasses, appear early and are followed by slender stalks terminating in spikes, or so-called ears, of grain. CLASSIFICATION Species of wheat are classified according to the number of chromosomes found in the vegetative cell. They are divided into three series: the diploid, or einkorn, containing 14 chromosomes; the tetraploid, or emmer, containing 28 chromosomes; and the hexaploid, containing 42 chromosomes. Wheat species crossbreed relatively frequently in nature. Selection of the best varieties for domestication took place over many centuries in many regions. VARIETIES According to the regions in which they are grown, certain types of ...

Plum (tree), fruit tree of a genus of the rose family, which also contains the other trees that produce drupes (hard-pitted fruits): peach, cherry, almond, and apricot. About 12 plum species are cultivated throughout temperate regions for their fruit and as flowering ornamentals. The trees are rarely more than 10 m (33 ft) high. The plum varieties, which are suited to both warm and cool climates, exceed the other drupes. The common European plum, the most important species, has been cultivated since ancient times and probably originated near the Caspian Sea. It was introduced into North America, possibly by the Pilgrims, and is now mostly cultivated in the western United States. Fruits of varieties of this species range in color from yellow or red to green, but purplish-blue is most common. Dried plums, or prunes, are made from the varieties that are richest in sugar and solids. The Japanese plum, probably originating in China, was introduced into the United States in 1870. The fruit ...

Apple, common name for certain related trees of the rose family, and for the pome fruit of the trees. The apple tree, a deciduous plant, grows mainly in the temperate areas of the world. The fruit is a firm, fleshy structure derived from the receptacle of the flower. Apple leaves are broadly oval in shape and are somewhat woolly on the undersides. The flowers in bloom have a rounded appearance. Some apple blossoms are white, but the majority of apple blossoms have stripes or tints of rose. A few apple species bloom with bright red flowers. Apple wood is hard, durable, and very fine-grained. The physical characteristics of the fruit are subject to considerable variation. The skin color may range from green to a deep, blackish red. Shapes, also, are diverse and include oblate and oblong fruits and fruits of a size hardly larger than a cherry or as big as a medium-sized grapefruit. Scientific classification: Apple trees belong to the family Rosaceae. They constitute the genus Malus.

Mango, common name for a tree, and for its fruit. The tree, which is native to India, grows up to 15 m (50 ft) high, with spreading top and numerous branches. It is widely grown in the tropics for its succulent fruit. The fruit, which is a fleshy drupe, is somewhat kidney-shaped or oval, from 5 to 15 cm (2 to 6 in) in length; greenish, yellowish, or reddish in color; and contains a large flattened stone. Scientific classification: The mango belongs to the family Anacardiaceae. It is classified as Mangifera indica.

Peach, common name for a deciduous orchard tree of the rose family, and for the fruit of this tree. The tree, which botanists believe is native to China, is cultivated throughout warm temperate and subtropical regions of the world. In the peach fruit, the stone is covered with a fleshy substance that is juicy, melting, and of fine flavor when matured and mellowed. The peach tree is of moderate height, more or less spreading according to variety, and, when left to itself, deep-rooted. The popular division of fruit varieties into clingstones and freestones—referring to the relative tendency of the flesh to cling to the stone—is by no means accurate. These two classes merge in different varieties, and even the same variety may be freestone and clingstone in different seasons. The nearly 300 varieties of peaches grown in America have been classified into five races, each with outstanding characteristics, ripening season, and uses. The nectarine is a variety of peach. The peach is not a ...