Glossary 621 



Congestion: An overloading of the capillaries and other blood vessels. 



Conjugation (kon-joo-ga'shwn) : A union of two cells for reproduction. 



Connective tissue: A collection of cells uniting other tissues. 



Conservation of energy: The law or principle that energy can neither 

 be created nor destroyed. 



Conservation of matter: The law or principle that matter cannot be 

 destroyed. 



Constellation (kon-st<?-la'shwn) : A group of stars having a special name. 



Constipation: Lack of adequate movement of the bowels. 



Contagious (kon-ta'jws) : Catching, as of a disease; communicable by 

 contact. 



Control: A standard, or check, for making comparisons; used in experi- 

 mental work. 



Convection (kon-vek'shwn) : The flow of heat through fluids by means 

 of heat currents. 



Convex (kon'veks) : Curved outward, as the outer surface of a ball. 



Coordination (ko-or-di-na'shwn) : The harmonious working together of 

 the different parts of the body. 



Cornea (kor'ne-a) : The transparent part of the outer coat of the eye, 

 which covers the iris and the pupil. 



Corona (ko-ro'nd) : A band of pearly light surrounding the sun. 



Corpuscles (kor'pus-'lz) : Minute cells in the blood. Red corpuscles 

 carry oxygen. White corpuscles destroy germs. 



Cosmic rays: A little known form of radiant energy which comes to 

 the earth from the space beyond our atmosphere. 



Cotyledon (kot-i-le'dwn) : A seed leaf or leaves of a young plant con- 

 taining food used to develop root, stem, and true leaves. 



Cultivation of soil: The plowing and harrowing of soil to break it up 

 so that it can better hold moisture, and to remove weeds. 



Culture: A growth of bacteria on a medium. 



Culture medium: A jelly-like substance on which bacteria are grown. 



Cumulus (ku'mu-lws) : A cloud form resembling heaps of wool; often 

 brings rain and thunderstorms. 



Current electricity: Flowing electricity. 



Cuspid (kus'pid) : A sharp, pointed tooth adapted for tearing; also called 

 canine. 



Cusps: The horns of the crescent moon. 



Cyclone: The whirl of the air around an area of low pressure. 



Cylinder: The chamber in a steam engine or gas engine in which ex- 

 panding steam or exploding gas forces the piston to move. 



Cytoplasm (sl'to-plaz'm) : The part of the protoplasm of a cell other 

 than the nucleus. 



Dam: A structure to hold back and store water for power, irrigation, 

 or home supply. 



Decay: To spoil, rot, or decompose; gradual loss of strength and sound- 

 ness. 



Decompose: To separate into simpler compounds or into elements; to 

 rot. 



Dehumidifier (de-hu-mid'i-fi-er) : A device for reducing the moisture 

 content, or humidity, of indoor air. 



Density: The closeness or compactness of the matter in a substance. 



Deodorant (de-6'der-ant) : A substance that destroys bad odors. 



