most important grains in the Middle East and
Europe; in Asia, rice; in the New World,
maize, or corn; in Africa sorghum and millets.
The grains are of special culinary significance
because they make possible beer and bread,
both staples in the human diet for at least
5,000 years.
An oat kernel, lentils in their pod, and a
hazelnut. All are seeds, and consist of a living
embryonic plant together with a food supply
to fuel its early growth. In the cereal grains,
the food supply is a separate tissue, the
endosperm. In the beans and their relatives,
and in most nuts, the food supply fills the first
two leaves of the embryo, the cotyledons,
which are unusually massive and thick.