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Related to Acrosome reaction: Cortical reaction, capacitation


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

ac′ro·so′mal (-sō′məl) adj.


(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]


(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.
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"
References in periodicals archive ?
Structural comparisons among glycosaminoglycans to promote an acrosome reaction in bovine spermatozoa.
In our experiments, cells appeared to be disrupted as they agglutinated, and this was likely due to an acrosome reaction. Sperm with reacted acrosomes or with damaged mitochondria can yield low fertilization rates.
Role of rabbit prostate granules on sperm viability and acrosome reaction evaluated with different methods.
Spermatozoa are capable of generating ROS (Aitken et al., 1997; Balla et al., 2001), and the controlled generation of ROS may have physiological functions in signaling events controlling sperm capacitation, acrosome reaction, hyperactivation and sperm-oocyte fusion.
Jelly coat and induction of the acrosome reaction in echinoid sperm.
Moreover, POEC and its conditioned medium efficiently increased the in vitro acrosome reaction of frozen-thawed bovine spermatozoa (23).
Acrosome reaction and viability were measured by a modified triple-stain technique described by Didion and Graves (1986).
In some groups these egg envelopes play a key role in the induction of the sperm acrosome reaction, sperm-egg binding, and the exclusion of supernumerary sperm (see reviews by Colwin and Colwin, 1967; Epel and Vacquier, 1978; Monroy and Rosati, 1983; Tilney, 1985; Longo, 1987; Sato and Osanai, 1990).
One possible hypothesis for this effect was the triggering of a premature acrosome reaction in sperms before they underwent full capacitation and maturation (31).
The critical concentration of ROS improved oocyte maturation and embryo development, and sperm function such as capacitation, hyperactivation and acrosome reaction (Viana et al., 2007; de Lamirande and O'Flaherty, 2008), but the high level of ROS in the in vitro culture system might induce apoptosis, also described as programmed cell death.