Conservation (noun) - According to The Dictionary of Science: The world of science: from Big Bang to biodiversity, conservation is the act of protecting and preserving the world from pollution, overexploitation, and other harmful human activities.
Zoo (noun) - According to The Dictionary of Science: The world of science: from Big Bang to biodiversity, zoo, an abbreviation for zoological gardens, is a place where animals are kept in captivity. Although zoos were originally created for human entertainment and education, today's zoos are playing an important conservation role by providing breeding opportunities for endangered species.
Zoology - According to The Dictionary of Science: The world of science: from Big Bang to biodiversity, the study of animals including descriptions of present-day animals, how animals have evolved, anatomy, behaviour, and geographical distribution.
History of Zoos
"Henry I started a royal menagerie at Woodstock, Oxfordshire (England), later transferred to the Tower of London. The Zoological Society of London was founded 1826 by Stamford Raffles in Regent's Park, London, and in 1827 the gardens were opened to members. In 1831 William IV presented the royal menagerie to the Zoological Society; the public were admitted from 1848. The name 'zoo' dates from 1867." From The Dictionary of Science: The world of science: from Big Bang to biodiversity, edited by Peter Lafferty and Julian Rowe. New York: Simon and Schuster, 1993.