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Related to Acrosomes: Acrosome reaction, Acrosomal process


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 ?
While six of the seven lectins failed to label the plasma membrane of sperm with intact acrosomes, all lectins intensely labeled the inner acrosomal membrane once it became exposed and accessible to the lectin.
The degree of staining was observed by phase contrast microscopy (400x) to determine the morphology of acrosomes. Acrosomes stained blue were considered normal, while the unstained acrosomes were considered abnormal.
Apparent differences in acrosomal contents suggest that species with open hull pores have simpler acrosomes than those with continuous hulls (Buckland-Nicks et al., 1990; Pash-chenko and Drozdov, 1998; Buckland-Nicks, 2008).
Two hundred spermatozoa were counted under a phase-contrast microscope (100 A-) for acrosomal integrity which was indexed as percentage of normal ruffled swollen or absent acrosomes (Ijaz et al.
To determine the potential effects of UVB on acrosomal integrity, three groups of UVB irradiated sperm were evaluated based on the presence of intact sperm acrosomes. To aid in distinguishing intact from disrupted acrosomes, sperm were labeled with 20 [micro]g/mL FITC-conjugated wheat germ agglutinin (WGA) (EY Laboratories, San Mateo, CA).
Acrosomes have been distinguished in the spermatozoa of fish species such as hagfishes (Jespersen, 1975; Alvestad-Graevner and Adam, 1977; Morisawa, 1995), lampreys (Stanley, 1967; Nicander and Szoden, 1971; Jaana and Yamamoto, 1981), elasmobranchs (Stanley, 1971), sturgeons (Cherr and Clark, 1984), lungfishes (Jespersen, 1971), and coelacanths (Mattei et al., 1988).
spermatozoa with intact acrosomes did not differ (Pgreater than0.05) in extender containing ascorbic acid, a-tocopherol and control at 1st, 3rd and 5th days of storage at 5degC.
This theory is supported by the localization of microfilaments both in egg microvilli (Burgess and Schroeder, 1977; Spudich and Amos, 1979; Tilney and Jaffe, 1980) and in sperm acrosomes (Tilney, 1975, 1978; Tilney et al., 1973); by the fertilization modifications of microfilament distribution, particularly in fertilization cones (Longo, 1978b, 1980; Tilney and Jaffe, 1980; Schatten and Schatten, 1980; Cline and Schatten, 1986); and by the blockage of fertilization by the inhibition of microfilament polymerization using cytochalasins (Gould-Somero et al., 1977; Longo, 1978a; Byrd and Perry, 1980; Schatten and Schatt en, 1980).
In this study, percentage of sperm with normal acrosomes remained similar in all experimental diluters on 1st, 3rd and 5th day of storage.
For example, shell valve structure and articulation is simpler and ties in well with the fossil record (Sirenko, 1997); also they are the only chitons known to have typical aquasperm with prominent acrosomes, and eggs with smooth hulls (Hodgson et at., 1988; 1989; Eernisse and Reynolds, 1994; Buckland-Nicks, 1995; Pashchenko and Drozdov, 1998).
The percentage of live sperm with intact acrosomes was 72.7+-4.2 in 0.5mM BHT as compared to values in extenders containing 0 (61.7+-1.5), 1.0 (64.3+-4.7), 2.0 (59.0+-2.0) and 3.0mM (59.0+-2.6) BHT.