{H zone}{}{Area in the center of the A band in which there are no actin myofilaments; contains only myosin.}
{hair follicle receptor}{}{A sensory receptor located in the structure in which hair develops.}
{Haversian system}{}{A central canal containing blood capillaries and the concentric lamellae around it; occurs in compact bone.}
{hemisphere}{}{Refers to half of the cerebrum of the brain.}
{hemoglobin}{}{Red, respiratory protein of erythrocytes; consists of 6% heme and 94% globin; transports oxygen and carbon dioxide.}
{hepatopancreatic ampulla}{}{Composed of the pancreatic duct and the common bile duct.}
{heterozygous}{}{Possessing two separate alleles of a gene.}
{holocrine}{}{Gland whose secretion is formed by the disintegration of entire cells [e.g., sebaceous gland; see also apocrine and merocrine].}
{homeostasis}{}{State of equilibrium in the body with respect to functions, composition of fluids and tissues.}
{homologous pair}{}{Pair of chromosomes each containing the same gene loci.}
{hormone}{}{Substance secreted by endocrine tissues into the blood that acts on a target tissue to produce a specific response.}
{human chorionic gonadotropin [HCG]}{}{Hormone produced by the embryo upon fertilization and division of embryonic cells. The hormone maintains the corpus luteum, which allows the uterine lining to proliferate.}
{hyaline cartilage}{}{Gelatinous, glossy cartilage tissue consisting of cartilage cells and their matrix; contains collagen, proteoglycans, and water.}
{hydrogen bond}{}{Hydrogen atoms bound covalently to either N or O atoms have a small positive charge that is weakly attracted to the small negative charge of other atoms such as O or N; can occur within a molecule or between different molecules.}