biology-dictionary_11-06-2009

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Calyx
Collectively, the sepals of a flower.
CAM photosynthesis
Crassulacean acid metabolism, also known as CAM photosynthesis, is an elaborate carbon
fixation pathway in some photosynthetic plants. CAM is usually found in plants living in arid
conditions, including cacti and pineapples.
CAM plant
A plant that uses crassulacean acid metabolism, an adaptation for photosynthesis in arid
conditions, first discovered in the family Crassulaceae. Carbon dioxide entering open
stomata during the night is converted into organic acids, which release CO 2 for the Calvin
cycle during the day, when stomata are closed.
Cambrian explosion
A burst of evolutionary origins when most of the major body plans of animals appeared in a
relatively brief time in geological history; recorded in the fossil record about 545 to 525
million years ago.
Cancer
A serious disease resulting from a malignant growth or tumour, caused by abnormal and
uncontrolled cell division.
Canine
One of the four pointed conical teeth located between the incisors and the premolars.
Canal system
A tube, duct, or passageway.
Capillary
A microscopic blood vessel that penetrates the tissues and consists of a single layer of
endothelial cells that allows exchange between the blood and interstitial fluid.
Capillary action
The movement of water or any liquid along a surface; results from the combined effect of
cohesion and adhesion.
Capillaries
Capillaries are the smallest of a body's blood vessels.

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