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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.


(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 ?
The morphological acrosome abnormality was assessed by viewing wet mount of diluted spermatozoa fixed in buffered Formalin-Citrate solution described by Weitze (1977).
In our experiments, cells appeared to be disrupted as they agglutinated, and this was likely due to an acrosome reaction.
5% eosin solution), mass activity (%, undiluted semen), motility (%, diluted with normal saline), progressive motility using an arbitrary scale of 1 to 5 (1, 2, 3, 4 or 5 = 10 to 25%, 25 to 50%, 50 to 70%, 70 to % 90 or 90 to 100% of the motile spermatozoa), viability (%, using eosin-nigrosin staining) and morphologically normal acrosome (%).
However, in this study the acrosome could not be seen on the anterior end at high magnifications, which was different from that reported for P.
A component of oviductal fluids, probably a glycosaminoglycan, is reported to positively affect bovine sperm capacitation and the acrosome reaction (Parrish et al.
For example, previous studies demonstrated that pretreatment of caprine spermatozoa with calcium ionophore treatment was more effective than heparin or caffeine pretreatment in promoting ability of spermatozoa to undergo the acrosome reaction (Pereira et al.
PTX increases cAMP level by a methylxanthine inhibition of phosphodiesterase and thus improves motility, capacitation and acrosome reaction (Yovich et al.
This is essential for in vitro fertilization (IVF) of mouse oocytes, and in its absence the acrosome reaction cannot occur (Lee and Storey, 1986).
Highly variable carbohydrate compositions of the egg outer coats have been reported in a broad spectrum of species, from invertebrates to vertebrates, that are known to serve functions in gamete recognition and/or acrosome reaction induction.
Because researchers cannot distinguish between sperm with and without acrosome caps, they must inject more than one sperm into an egg in order to get a decent shot at fertilization -- a practice that sometimes produces useless, polyspermic eggs, says Lippi.
During the fertilization process, specific protein-degrading enzymes are added to the acrosomal membrane of spermatozoa in the epididymis, and spermatozoa are capacitated by the uterine environment and hormones, thereby completing the acrosome reaction (Phelps et al.
Moreover, POEC and its conditioned medium efficiently increased the in vitro acrosome reaction of frozen-thawed bovine spermatozoa (23).