Multiracial peopleMultiracial people or mixed-race people are people of more than one race. A variety of terms have been used both historically and presently for mixed race people in a variety of contexts, including multiethnic, polyethnic, occasionally bi-ethnic, Métis, Muwallad, Colored, Dougla, half-caste, ʻafakasi, mestizo, mutt, Melungeon, quadroon, octoroon, sambo/zambo, Eurasian, hapa, hāfu, Garifuna, pardo, and Gurans. A number of these terms are now considered offensive, in addition to those that were initially coined for pejorative use.
HeterosisHeterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of its parents. The heterotic offspring often has traits that are more than the simple addition of the parents' traits, and can be explained by Mendelian or non-Mendelian inheritance. Typical heterotic/hybrid traits of interest in agriculture are higher yield, quicker maturity, stability, drought tolerance etc.
The Extended PhenotypeThe Extended Phenotype is a 1982 book by the evolutionary biologist Richard Dawkins, in which the author introduced a biological concept of the same name. The book’s main idea is that phenotype should not be limited to biological processes such as protein biosynthesis or tissue growth, but extended to include all effects that a gene has on its environment, inside or outside the body of the individual organism. Dawkins considers The Extended Phenotype to be a sequel to The Selfish Gene (1976) aimed at professional biologists, and as his principal contribution to evolutionary theory.
Resource (biology)In biology and ecology, a resource is a substance or object in the environment required by an organism for normal growth, maintenance, and reproduction. Resources box can be consumed by one organism and, as a result, become unavailable to another organism. For plants key resources are light, nutrients, water, and place to grow. For animals key resources are food, water, and territory. Terrestrial plants require particular resources for photosynthesis and to complete their life cycle of germination, growth,
Race and societySocial interpretations of race regard the common categorizations of people into different races, often with biologist tagging of particular "racial" attributes beyond mere anatomy, as more socially and culturally determined than based upon biology. Some interpretations are often deconstructionist and poststructuralist in that they critically analyze the historical construction and development of racial categories.
AmenorrheaAmenorrhea is the absence of a menstrual period in a female who has reached reproductive age. Physiological states of amenorrhoea are seen, most commonly, during pregnancy and lactation (breastfeeding). Outside the reproductive years, there is absence of menses during childhood and after menopause. Amenorrhoea is a symptom with many potential causes. Primary amenorrhea is defined as an absence of secondary sexual characteristics by age 13 with no menarche or normal secondary sexual characteristics but no menarche by 15 years of age.
