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Related to acrosome: cortical granule


A caplike structure at the anterior end of a spermatozoon that produces enzymes aiding in egg penetration.

ac′ro·so′mal (-sō′məl) adj.
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.


(Physiology) a cap-like structure on the tip of a spermatozoon that releases enzymes on encountering the ovum allowing fusion with the ovum in the sexual reproductive process; this part of the process is known as the acrosome reaction
[C19: from acro- + -some3]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈæk rəˌsoʊm)

an organelle covering the head of animal sperm and containing enzymes that digest the egg cell coating, thus permitting the sperm to enter the egg.
[1895–1900; < German Akrosoma; see acro-, -some3]
ac`ro•so′mal, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.acrosome - a process at the anterior end of a sperm cell that produces enzymes to facilitate penetration of the eggacrosome - a process at the anterior end of a sperm cell that produces enzymes to facilitate penetration of the egg
sperm, sperm cell, spermatozoan, spermatozoon - the male reproductive cell; the male gamete; "a sperm is mostly a nucleus surrounded by little other cellular material"
appendage, outgrowth, process - a natural prolongation or projection from a part of an organism either animal or plant; "a bony process"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Use of a triple-stain technique to detect viability and acrosome reaction in deer spermatozoa.
CRISP2 protein is located in the acrosome and the outer dense fibers of the sperm tail (19-23).
Sperm motility decreased, acrosome reactions failed to occur and worst of all, sperm counts dropped' and the function of the Sertoli or 'support' cells that create key proteins to sperm production declinees, she explained.
Sperm cells are elongated, with half of their length corresponding to the acrosome (a = 4.76[+ or -]0.14 [micro]m) and the other half to the lamellar region arms or spines (s = 11.16 [+ or -] 0.2 [micro]m).
Percent live spermatozoa, percent membrane integrity, percent acrosome integrity and percent normal spermatozoa were determined using standard protocols.
In mice, the success of ICSI could be improved by the removal of both sperm membranes and acrosome before injection (23).
This method can better determine the size and position of spermatid acrosomes. Using this latter approach, characterization of the seminiferous epithelium stages is determined based on the presence, angle, and size of the acrosome, shape and location of spermatid nuclei, presence of meiotic division, and overall components of the testicular seminiferous epithelium.
It is intriguing to speculate that acrosomal leptin receptor expression is associated with cholesterol efflux and acrosome reaction, whereas tail leptin receptor expression in human sperm may reflect leptin's modulation of hyperactivated sperm motility.
Besides, PICK1 influences the progress of acrosome biogenesis, and its deficiency is accompanied by increased apoptosis [15].