biology-dictionary_11-06-2009

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Cork cambium
A cylinder of meristematic tissue in plants that produces cork cells to replace the epidermis
during secondary growth.
Corolla
Petals, collectively; usually the conspicuously colored flower parts.
Corpuscle
Any of various cellular or small multicellular structures in the body, especially a red or white
blood cell.
Corpus callosum
In the vertebrate brain, a tightly packed mass of myelinated nerve fibers connecting the two
cerebral hemispheres.
Corpus lutuem
A secreting tissue in the ovary that forms from the collapsed follicle after ovulation and
produces progesterone.
Corpuscles
A rounded globular mass of cells, such as the pressure receptor on certain nerve endings.
Cortex
(1) The outer, as opposed to the inner, part of an organ, as in the adrenal gland. (2) In a
stem or root, the primary tissue bounded externally by the epidermis and internally by the
central cylinder of vascular tissue.
Cortisol
A steroid hormone, produced by the adrenal cortex, that promotes the formation of glucose
from protein and fat; also suppresses the inflammatory and immune responses.
Cotransport
The coupling of the "downhill" diffusion of one substance to the "uphill" transport of
another against its own concentration gradient.
Cotyledon
The one (monocot) or two (dicot) seed leaves of an angiosperm embryo.
Countercurrent exchange
The opposite flow of adjacent fluids that maximizes transfer rates; for example, blood in the
gills flows in the opposite direction in which water passes over the gills, maximizing oxygen
uptake and carbon dioxide loss.

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