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In

(Encyclopedia)In, symbol for the element indium. ...

genetic testing

(Encyclopedia)genetic testing, medical screening for genetic disorders, by examining either a person's DNA directly or a person's biochemistry or chromosomes for indirect evidence. Testing may be done to identify a...

eugenics

(Encyclopedia)eugenics yo͞ojĕnˈĭks [key], study of human genetics and of methods to improve the inherited characteristics, physical and mental, of the human race. Efforts to improve the human race through bette...

reproductive system

(Encyclopedia)CE5 Reproductive system reproductive system, in animals, the anatomical organs concerned with production of offspring. In humans and other mammals the female reproductive system produces the femal...

infertility

(Encyclopedia)infertility, inability to conceive or carry a child to delivery. The term is usually limited to situations where the couple has had intercourse regularly for one year without using birth control. The ...

pregnancy

(Encyclopedia)pregnancy, period of time between fertilization of the ovum (conception) and birth, during which mammals carry their developing young in the uterus (see embryo). The average duration of pregnancy in h...

Hertwig, Oscar

(Encyclopedia)Hertwig, Oscar ôsˈkär hĕrtˈvĭkh [key], 1849–1922, German embryologist. He studied medicine with Haeckel and Gegenbaur. In 1875 he established the fact that fertilization consists of the union ...

Kölreuter, Joseph Gottlieb

(Encyclopedia)Kölreuter or Koelreuter, Joseph Gottlieb both: yōˈzĕf gôtˈlēp kölˈroiˌtər [key], 1733–1806, German botanist. In 1764 he became professor of natural history and director of the botanical g...

progesterone

(Encyclopedia)progesterone prōjĕsˈtərōnˌ [key], female sex hormone that induces secretory changes in the lining of the uterus essential for successful implantation of a fertilized egg. A steroid, progesterone...

Spallanzani, Lazzaro

(Encyclopedia)Spallanzani, Lazzaro lädˈdzärō späl-läntsäˈnē [key], 1729–99, Italian naturalist. He was professor at the universities of Modena (1763–69) and Pavia (from 1769). Spallanzani studied regen...