GLOSSARY 



Absorption (Lat. absorbere, to swallow down): the process by which liquid food or 

 other substances are taken through cell wails. 



Adaptation (Lat. adaptere, to fit): changes in organisms which fit them to their environ- 

 ment. 



Afferent (Lat. ad, to; jero, bear) fibers: those conveying stimuli to sense organs, brain 

 or spinal cord. 



Albu'men (Lat. albumen, white of egg): protein residing in white of egg. 



Allan'tois (Gr. alias, sausage; eidos, form): membranous organ growing out of the hind 

 gut in the embryos of reptiles, birds and mammals, and serving for respiration 

 and excretion. 



Altricial (Lat. altrix, nurse) : birds that are helpless on hatching. 



Am'nion (Gr. amnos, a lamb): membranous sac which encloses the embryos of reptiles, 

 birds and mammals. 



Amphib'ian (Gr. amphi, both; bios, life): animals able to live on land and water. 



Anat'omy (Gr. ana, up; temno, cut): the science of gross bodily structure. 



Ar'tery (Gr. aer, air; tereo, keep): vessels conveying blood from the heart to the organs. 



Ax'on (Gr. axon, axis): main outgrowth of a neuron. 



Blas'tomere (Gr. blastos, embryo; meros, part): a cell produced by segmentation of a 

 fertilized egg. 



Blas'topore (Gr. blastos, embryo; poros, passage): the external opening of a gastrula. 



Bias 'tula (Gr. blastos, germ): the stage at the end of segmentation when the embryo 

 is a hollow sphere with no opening. 



Bronchus, pi. bronchi (Gr. bronchos, windpipe) : one of the two large subdivisions of the 

 trachea. 



Calorie (Lat. calere, to be hot) : amount of heat required to raise one kilogram of water 

 one degree Centigrade. 



Capillary (Lat. capillus, a hair): the microscopic blood vessels uniting arteries with 

 veins. 



Carbohy'drate (Lat. carbo, coal; Gr. hydro, water): food stuffs made of carbon, hydro- 

 gen and oxygen, the hydrogen and oxygen being in the same proportion as water. 



Carniv'orous (Lat. caro (carnis), flesh; vo'rare, to eat): flesh-eating animals and plants. 



Car'tilage (Lat. cartilago, gristle): the elastic animal tissue forming parts of organs or 

 bones. 



Caud'al (Lat. cauda, tail): pertaining to the tail. 



Cell (Lat. cella, a small room): the unit of living things. A mass of protoplasm in- 

 closing a nucleus, and usually inclosed in a cell wall. 



Cellulose (Lat. cellula, a little cell): an organic substance found in the walls of plant 

 cells, and in the Tunicates. 



Cere (Lat. cera, wax): a fleshy growth at the base of the bill of some birds. 



Chitin (Gr. chiton, a gown or tunic) : the outer covering of the bodies of insects and 

 other animals. 



Chlor'ophyll (Gr. chloros, green; phullon, leaf): the green substance enabling green 

 plants to utilize sunlight to build up food. 



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