Buds and Budding
Buds and budding are also found in the asexual reproduction (involving only one parent) of some animals, such as the freshwater hydra and species of marine colonial jellyfish, where a single parent gives rise to one or more new individuals. When a single hydra reaches maturity and is well fed, outpocketings of the animal's body wall begin to form a rounded growth projecting from the tube-like section or stalk of the adult's body. This growth, called a bud, develops in time into a miniature hydra whose body layers and inner body cavity, the digestive cavity, are continuous with that of the parent individual. Food captured and gathered in by the adult parent also supports the growth of the bud. Early in this budding process tiny tentacles appear on the free end of the hydra bud. It is not unusual to find two or more buds on an adult hydra in different stages of growth and development. An adult hydra may have its body and tentacles fully extended while its bud may have its whole form contracted into a rounded mass. Conversely the bud may be stretched out, while the adult is contracted. The bud will, however, sometimes contract soon after the adult contracts as the nerve net in the mesoglea (middle jelly layer) of the two individuals is continuous. When a newly budded hydra offspring is fully formed and sufficiently developed to take up an independent existence, the base of the new hydra seals off and thus allows the new individual to break off from the parent hydra.
Buds and budding also refers to the extensions of microscopic yeast cells and some types of bacterial cells produced during asexual reproduction, forming the beginning of daughter cells. The taste buds of the mammalian tongue, are so called because of their small size and bud-like shapes, but bear no relationship to the buds of plants and animals discussed above.
Campbell, N., J. Reece, and L. Mitchell. Biology. 5th ed. Menlo Park: Benjamin Cummings, Inc. 2000.
Raven, Peter, R.F. Evert, and Susan Eichhorn. Biology of Plants. 6th ed. New York: Worth Publishers Inc., 1998.
Julia M. Van Denack