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artificial insemination – n. a medical process in which male reproductive fluid is used to make a woman or female animal pregnant without sex
species – n.
extinction – n. the state or situation that results when something (such as a plant or animal species) has died out completely
hormone – n. a substance produced in a living organisms and transported in tissue fluids
semen – n. the sticky, whitish liquid that is produced by a male's sex organs
embryo – n. a human or animal in the early part of development
