SS2 GLOSSARY 



Photosyn 'thesis (Gr. p/tos, light; synthesis, nutting together): food-making by green 



plants in presence of sunlight. 

 Phylum (plural phyla) (Gr. phulon, tribe): one of the main groups of the animal king- 

 dom; about twelve groups are recognized. 

 Physiol 'ogy (Gr. physis, nature; logos, discourse): the study of the life processes of 



organisms. 

 Pin'eal (Lat. pinea, a pine cone): an organ of doubtful function situated anterior to the 



corpora quadrigemina of the brain. 

 Plas'ma {Gr. plasma, formative material): the liquid portion of the blood of vertebrates. 

 Plecop'tera (Gr. plectos, plaited; />/fro«, wing) : an order of insects having plaited wings, 



as stone flies. 

 Poi'son (Lat. potto from poto, drink): any substance harmful to the system of an 



organism. 

 Polyp (Gr. polus, many; pons, foot): the sessile type of Coelenterate having numerous 



tentacles. 

 Por'tal (Lat. porta, gate) vein: the large vein that carries blood to the liver. 

 Pro'tein (Gr. protos, first): a compound of oxygen, hydrogen, carbon and nitrogen, with 



traces of other elements. 

 Pseudopod'ium (Gr. pseudes, false; pous, foot): a projection of protoplasm used by 



protozoons for locomotion. 

 Pro'toplasm' (Gr. protos, first; plasma, form): the physical basis of life; the living sub- 

 stance contained in organisms. 

 Pro'tozoon (plural protozoa) {Gv. protos, first; zoon, animal): a unicellular animal. 

 Pty'alin (Gr. ptyalon, spittle): the enzyme in saliva changing starch to sugar. 

 Pylor'us (Gr. pyloros, gate-keeper): stomach-intestinal opening. 

 Rapto'res (Lat. rapere, to ravish) : an order of birds having sharp hooked beaks and 



strong, sharp talons; birds of prey. 

 Reces'sive (Lat. re, back; cedo, yield) characters: those not appearing in a hybrid, 



owing to the dominance of other characters. 

 Rec'tum (Lat. rectus, straight): the terminal portion of the alimentary canal. 

 Re 'flex (Lat. re, hack; ^ecto, bend) action: non-mental action. 

 Re 'genera 'tion (Lat. re, again; genero, beget): restoration of a lost part by growing a 



new one, as the tentacle of a hydra. 

 Reproduc'tion (Lat. re, again; pro, before; duco, lead): begetting like; like producing 



like. 

 Respira'tion (Lat. re, again; spiro, breathe): oxidation of protoplasm releasing energy 



and producing carbon dioxide. 

 Ret'ina (Lat. rete, net): the black inmost layer of the eyeball which receives the stimuli 



of light rays and conducts them to the brain through the optic nerve. 

 Ru'minant (Lat. rumen, throat): an animal which chews its cud, as cow. 

 Sali'va (Lat. saliva, spittle): the natural moisture in the mouth secreted by the salivary 



glands. 

 Sclerot'ic (Gr. skleros, hard) coat: the tough outer coat of the eyeball. 

 Scute (Lat. scutum, scale): one of the large scales on the snake's abdomen. 

 Scutel'lum (Lat. dim. oi scutum, shield): the shield-shaped cotyledon lying under the 



embryo in grains. 

 Sex ual (Lat. sexus, sex) reproduction: a new individual arising from the union of an 



egg and sperm. 



