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ovum
(Encyclopedia)ovum ōˈvəm [key], in biology, specialized plant or animal sex cell, also called the egg, or egg cell. It is the female sex cell, or female gamete; the male gamete is the sperm. The study of the ovu...animal
(Encyclopedia)animal, any member of the animal kingdom (kingdom Animalia), as distinguished from organisms of the plant kingdom (kingdom Plantae) and the kingdoms Fungi, Protista, and Monera in the five-kingdom sys...ovary
(Encyclopedia)ovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control t...multiple birth
(Encyclopedia)multiple birth, bringing forth of more than one offspring at birth. Although many smaller mammals bear several young at a time, multiple births are relatively uncommon in humans and other primates. Tw...animal husbandry
(Encyclopedia)animal husbandry, aspect of agriculture concerned with the care and breeding of domestic animals such as cattle, goats, sheep, hogs, and horses. Domestication of wild animal species was a crucial achi...animal jelly
(Encyclopedia)animal jelly: see gelatin.moss animal
(Encyclopedia)moss animal, common name applied to members of the phylum Ectoprocta. ...in vitro fertilization
(Encyclopedia)in vitro fertilization vēˈtrō, vĭˈtrō [key] (IVF), technique for conception of a human embryo outside the mother's body. Several ova, or eggs, are removed from the mother's body and placed in sp...uterus
(Encyclopedia)uterus, in most female mammals, hollow muscular organ in which the fetus develops and from which it is delivered at the end of pregnancy. The human uterus is pear-shaped and about 3 in. (7.6 cm) long ...animal-rights movement
(Encyclopedia)animal-rights movement, diverse individuals and groups concerned with protecting animals from perceived abuse or misuse. Supporters are specifically concerned with the use of animals for medical and c...Browse by Subject
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