710 - Index 



Host, effects of parasitism on, 578 



Hotrhkiss, R.. 520-21 



Human being (.sec Man) 



Hunger, sense of, 426 



I Iun\ itz, [., 525, 526 



Huxley, A. F„ 437 



Huxley, H. E„ 437 



Hybrids, 482 



Hydra, 55, 56, 296, 357, 380, 381, 396, 632-33; 



cellular structure of, 632; nerve net of, 449-50; 



saccular digestive system of, 292-95 

 Hydrogen, 65, 141-42, 145: sensitivity of cnzviius 



to, 109 

 I lydrogen ace eptor, 145 

 Hydrogen bonds, 87, 521-22 

 1 Ivdrogen eve le, 1 83 

 I lydrogen ions, 73 

 I lydrogen peroxide 1 , 99 

 Hydrolases, 101, 102-03 

 Hydrolysis, 79, 81, 84, 138-39 

 Hydrophytes, 586 

 Hydrotropism, 263, 264 

 I lydroxyapatite. 406 

 I Ivdroxvl ions, 73 

 Hydrozoa, 632-33 

 HymenojHcra, 658 

 1 lyperglye emia. 34 1 

 I Ivpc rtension. 376) 

 Hyphae, 173, 175 

 llvpocotyl. 223, 230 

 Hypoglycemia, 34 I 

 Hypoinsulinism, 408-09 

 Hypothalamus, 41 3 

 Hypothesis, in scientific method, !3- I 

 Hypothyroidism, 346, 403-05 



I 



Identical twins. 395, 499, 502, 510 



Ileocaecal sphincter, 315 



Ileum, 31 1 



Imbalance in an ecosystem, 589 



Impulses, localization of, 464 



Inbreeding. 481, 499. 516 



Incipient colonies, 55 



Incomplete linkage, 491-93 



Incubation period ol viruses, 8 



Independent assortment, breeding experiments, 



487-89; Mendel's law of, 490 

 Indie ator dyes, 74 

 Indirect calorimetrv, 344 

 Inflorescences, 225, 226, 227 

 Infundibulum, 409, 410 

 Ingenhousz, J., 159 

 Ingestion, 128-29 

 Inguinal canal. 383 

 Inguinal hernia, 383 



Inheritance, biparental, 51, 55: blended, 509; in 



man, 504-10; Mendelian, 481-84; particulate, 



548; of sex, 495-99. See also Heredity 

 Inhibitors, plant, 265 

 Inorganic substances, organic vs., 71; protoplasm 



components, 71-75 

 Insecta, 655; behavior, 660; insect societies, 658- 



60; orders of, 658 

 1'i.st't t'woru, 675 

 i scctivorotts plants. 261 

 Insemination, 274 



Insertion of skeletal muscles, 131, 432 

 Insulin, 341. 375, 408, 417 

 Intercellular cement, 34 

 1 uicrccllular matrix, 34 

 1 tercellular spaces, 243 

 Intercerebral gland. 417 

 Intermediary metabolism. 141 

 Intermitotic period, 50 

 Intermolecular fit, concept of, 106 

 Internal fertilization, 381-83 

 Internal respiration, 357, 364 

 lnternodes. 237 



Interpretation, in scientific method, 13 

 Interstitial cells. 383. 385 

 Intestinal glands. 297. 298. 310 

 Intestinal juice. 297, 298. 314 

 Intestine. 296. See also Colon; Small intestine 

 Intracellular structure. 21-22 

 Intromittent organ, 381, 385-86 

 Invagination, 278 

 Iodopsin, 424 

 Ion carrier molecules, 123 

 Ionic transport mechanisms, 123-24 

 Ions, 73: hydrogen, 73; hydroxy!, 73; inorganic, 



in protoplasm, 74—75; sensitivity of enzymes 



to, 109 

 Irish moss, 601 

 Islands of Langerhans, 408 

 Isogametes, 58. 61, 596 

 Isogamy, 57-59 

 Isolation, 545 

 Isoleucine, 135 

 Isoplera, 658 

 Isotonic solutions, 118 

 Isotopes, atomic. 65 n.: metabolic tracers, 141-42; 



radioactive. 255 



J 



anus green dye, 28 

 ava man, 571 

 ejunum, 31 1 

 elly fishes, 633 

 ohnson, F. H., 142 

 urassic period, 563, 565 

 uvenile hormone, 414 



