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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...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...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 ...fertilization
(Encyclopedia) CE5 Fertilization of an egg cell fertilization, in biology, process in the reproduction of both plants and animals, involving the union of two unlike sex cells (gametes), the sperm and the ovum, f...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...egg
(Encyclopedia)egg: see ovum.meiosis
(Encyclopedia) CE5 Formation of sperm cells through meiosis meiosis mīŏˈsĭs [key], process of nuclear division in a living cell by which the number of chromosomes is reduced to half the original number. Meio...sperm
(Encyclopedia)sperm or spermatozoon spûrˌmətəzōˈən, –zōˈŏn [key], in biology, the male gamete (sex cell), corresponding to the female ovum in organisms that reproduce sexually. In higher animals the spe...Browse by Subject
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