Herpes, 994
Hershey, Alfred, 340–341, 349
Heterotrophic protists, 612–613
Heterotrophs, 71, 228, 250, 527
Heterozygous organisms, 314
Hibernation, 847
High-altitude adaptation, 831
High-density lipoprotein (HDL), 959
Histamines, 938, 1014
Histones, 280, 352
HIV, 578, 589, 1023, 1026–1027
Homeobox genes, 382
Homeostasis, 19–20
in animals, 732, 827–830
and blood glucose levels, 978, 984
and breathing, 967
and cells, 214–217
and endocrine system, 828, 986–987
in humans, 865–867, 886–887
and kidneys, 886–887
and pH, 44
of plants, 682–683, 711
and skin, 935, 937
Homeotic genes, 382
Hominines, 767–772
Hominoids, 767
Homo erectus, 771
Homo ergaster, 770
Homo habilis, 770–771
Homologous chromosomes, 323–325, 327
Homologous proteins, 471
Homologous structures, 468–469
Homo neanderthalensis, 772, 773
Homo sapiens, 767, 770, 772, 773
Homozygous organisms, 314
Hooke, Robert, 190
Hormone receptors, 709, 980
Hormones, 978
Hornworts, 641
Hoxc8, 470
Hox genes, 382, 471, 500–501
Human activity, 154–156, 173–174, 183. See also Resources, natural
Human body
circulatory system, 734, 791, 793, 948–953, 957–961, 963
digestive system, 737, 864, 875–881
embryonic development, 988, 995–999
endocrine system, 828, 864, 978–987
excretory system, 882–887
fetal development and childbirth, 999–1001
and homeostasis, 865–867, 886–887
integumentary system, 864, 935–939
levels of organization of, 862–864
lymphatic system, 864, 956–957
muscular system, 864, 928–933, 940
nervous system, 896–908
and nutrients, 868–873, 880
organs in, 863
reproductive system, 864, 988–993
respiratory system, 963–969
sense organs, 909–913
skeletal system, 864, 922–927
specialized cells in, 862
tissues in, 862–863
and water, 869, 986
Human Genome Project, 406–409, 430
Human growth hormone (HGH), 3, 29, 430
Human heredity, 392–409
Human immunodeficiency virus (HIV), 578, 589, 1023, 1026–1027
Human papillomavirus (HPV), 588–589, 994
Human populations. See also Populations
Humoral immunity, 1016–1018
Huntington's disease, 399
Hutton, James, 454–455, 459, 467
Hybridization, 419
Hybrids, 309
Hydras, 754, 814
Hydrochloric acid, 44
Hydrogen, 35, 51
Hydrogen bonds, 41, 348
Hydrogen ions, 43–44
and cellular respiration, 258
and photosynthesis, 236–237
Hydrophilic molecules, 204
Hydrophobic molecules, 204
Hydrostatic skeleton, 814
Hypercholesterolemia, 973
Hypertension, 887, 959
Hyperthyroidism, 985
Hypertonic solutions, 210–211
Hyphae, 619
Hypodermis, 936
Hyponatremia, 221
Hypothalamus, 866, 903, 979, 982, 986–987
Hypothesis, 7, 9
Hypothyroidism, 985
Hypotonic solutions, 210–211
I
Iceman, 633, 659
Ichthyosaur, 536–537
Identical twins, 996
Immigration, 132
Immune response, 1016–1018
Immune system, 828, 864
Immunity, 588
Implantation of embryo, 996
Imprinting, 844–845
Impulses, 897–900
Inbreeding, 419
Incisors, 785
Incomplete dominance, 319
Independent assortment, principle of, 317–318, 328–329
Independent variable, 7
Index fossils, 540
Infant mortality, 1001
Infectious diseases, 23, 1010–1023. See also Diseases, causes of, 1010–1011
Inference, 7
Inflammation, 927
Inflammatory response, 1014
Influenza, 575, 588–589, 591, 1010
Ingenhousz, Jan, 229
Ingestion, 875