Flowering plants can be broken into two types, monocots and dicots. Due to differences in the way these seeds germinate, monocot corn seeds and dicot bean seeds are often studied and compared in plant biology classes.
The main difference between monocots and dicots is the number of cotyledons, or embryonic leaves inside of the seed. As a monocot, corn seeds will produce a seedling with one leaf. Bean seeds, which are dicots, will sprout with two leaves.
Since monocots, such as the corn seed, only have a single leaf inside, most of the space inside the seed is reserved for endosperm -- a food source used by the seedling as it germinates. When corn seedlings emerge only a single leaf pokes through the soil. Bean plants, on the other hand, have two cotyledons, both of which store and provide food to the seedling in absence of a wealth of endosperm. Bean cotyledons emerge from the soil with the seedling and feed it as it grows.
Corn germinates in about three days, while beans take about seven days to germinate. Both are summer vegetables and require warm soil conditions to grow.
Corn and beans are companion plants. Plant pole beans between corn and the beans can use corn stalks as a trellis.