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Related to polar nucleus: antipodal cells
Either of two nuclei in the embryo sac of a flowering plant that fuse with each other and with a male gamete to form the primary endosperm nucleus.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
either of two female haploid nuclei, in the embryo sac of flowers, that fuse to produce a diploid nucleus.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.