These structures have been installed and operated for a number of reasons: 1  locks allow navigation on large rivers to facilitate boating traffic. 2  weirs create pool environments for diversion into irrigation channels, for pump intakes, recreational boating and swimming, and other aesthetic reasons.
Medical Definition of carbohydrate. : any of various neutral compounds of carbon, hydrogen, and oxygen (as sugars, starches, and celluloses) most of which are formed by green plants and which constitute a major class of animal foods.
A carbohydrate is a biological molecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogenâoxygen atom ratio of 2:1 (as in water); in other words, with the empirical formula Cm(H2O)n (where m could be different from n).