564 GLOSSARY 



Cytoplasm (si'-to-plazm), cell material lying between the nucleus and the outer 

 plasma membrane. 



Dermal (dilr'-mal), pertaining to skin. 



Diabetes (di'-a-be-tez), disease caused by deficiency of insulin. 



Diaphragm (di'-a-fram), a muscular partition separating the thoracic and ab- 

 dominal cavities in mammals. 



Diencephalon (dl-en-sef'-a-lon), the second portion of the brain of vertebrates, 

 often called the thalamus in man. 



Dimorphism (di-mor'-fizm), two forms within the same species. 



Dinosaur (di'-no-sor), extinct reptile that dominated the earth during the 

 mesozoic era. 



Diploblastic (dip-l5-blas'-tik), having two germ layers in the body. 



Diverticulum (di-ver-tik'-Q-lum), pi. -la, a small intestinal branch as found 

 in Planaria. 



Duodenum (du-o-de'-num), the first loop of the small intestine in vertebrates. 



Dysentery (dis'-en-ter-i), a disease of the colon characterized by diarrhea; one 

 form caused by an Endamoeba. 



Ecology (e-kSl'-o-ji), a phase of biology dealing with the living organism in 



relation to its environment. 

 Ecto- (ek'-to), prefix referring to outside. 



Ectoderm (ek'-to-durm), the outer germ layer of animal bodies. 

 Egestion (e-jes'-chun), the elimination of indigestible food waste. 

 Elephantiasis (el-e-fan-ti'-a-sis), a disease involving great enlargement of vari- 

 ous body parts. 

 Embryology (em-bri-ol'-o-ji), a phase of biology dealing with the development 



of the individual from its earliest beginning until it reaches the adult type. 

 Encyst (en-sist'), the development of a cyst around the outside of an organism 



or part of an organism. 

 Endo- (en'-do), prefix referring to "inside". 

 Endocrine (en'-dS-knn), pertaining to a series of glands in the bodies of higher 



animals whose secretions are spread over the body by blood and lymph 



rather than by ducts. 

 Endoderm (en'-do-durm), the inner germ layer of animal bodies. 

 Endopodite (en-dop'-o-dit), the inner and main branch of a biramous appendage. 

 Enteric en-ter'-ik), refers to the intestines. 

 Enterocoel (en'-ter-o-sel), a body cavity formed by an outpocketing of the 



primitive gut or enteron. 

 Entomology (en-to-mol'-o-ji), a study of insects. 

 Enzyme (en'-zim), a substance secreted by cells that has the power to produce 



chemical changes in some specific substance, such as changing starch to 



sugar. 

 Epipodite (ep-ip'-o-dit), a dorsal branch attached to a biramous appendage. 

 Epithelium (epi-thel'-i-um), a sheet-like group of cells covering an external or 



internal surface of the body. 

 Erythrocyte (e-nth'-r5-sit), red blood corpuscle. 



Esophagus (e-sof'-a-gus), a tube at the anterior part of the digestive tract. 

 Estrogen (es'-tro-jen), female hormone secreted by the follicles of the ovaries. 

 Eustachian (u-sta'-ki-an), a tube connecting the middle ear to the pharynx. 

 Evagination (e-vag-i-na'-shun), an outgrowth from a cavity. 



