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larva, in zoology

(Encyclopedia)larva, independent, immature animal that undergoes a profound change, or metamorphosis, to assume the typical adult form. Larvae occur in almost all of the animal phyla; because most are tiny or micro...

drug resistance

(Encyclopedia)drug resistance, condition in which infecting bacteria can resist the destructive effects of drugs such as antibiotics and sulfa drugs. Drug resistance has become a serious public health problem, sinc...

embryo

(Encyclopedia)CE5 Development of the human embryo embryo ĕmˈbrēō [key], name for the developing young of an animal or plant. In its widest definition, the embryo is the young from the moment of fertilizatio...

Huxley, Sir Julian Sorell

(Encyclopedia)Huxley, Sir Julian Sorell, 1887–1975, English biologist and writer, educated at Oxford; grandson of Thomas Henry Huxley, brother of Aldous Huxley, and half-brother of Sir Andrew Huxley. He taught at...

Great Limpopo Transfrontier Park

(Encyclopedia)Great Limpopo Transfrontier Park, c.13,500 sq mi (35,000 sq km; roughly the size of Belgium), the largest multinational park in S Africa and one of the largest parks in the world, in NE South Africa, ...

guinea pig

(Encyclopedia)guinea pig gĭnˈē [key], domesticated form of the cavy, Cavia porcellus, a South American rodent. It is unrelated to the pig; the name may refer to its shrill squeal. Guinea pigs were raised by the ...

onager

(Encyclopedia)onager ŏnˈəjər [key] or Persian wild ass, wild ass of central Asia, Equus hemonius onager. Formerly classified as a separate species, it is one of the several subspecies of Asian wild ass (E. hemo...

artificial insemination

(Encyclopedia)artificial insemination, technique involving the artificial injection of sperm-containing semen from a male into a female to cause pregnancy. Artificial insemination is often used in animals to multip...

Wilmut, Sir Ian

(Encyclopedia)Wilmut, Sir Ian, 1944– British embryologist, b. Warwickshire, England, Ph.D. Cambridge, 1971. While doing postdoctoral research at Cambridge, he was part of the team that produced Frostie, the first...

wisent

(Encyclopedia)wisent vēˈsənt [key], name for the European bison, Bison bonasus. It is a close relative of the American bison, B. bison. Longer legged and less heavily built than its American cousin, the wisent m...