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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.


(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 ?
Cryopreservation causes permanent functional damage to sperm viability that can be explained partially by the reduction in the percentage of normal intact acrosomes and in total acrosin activity.
Two hundred heads of spermatozoa per slide were counted for acrosome abnormalities such as swollen, ruffled or absent acrosomes.
Therefore reduced level of oxidative stress in frozen thawed spermatozoa treated with SP-HBP may be responsible for higher percentage of motile, viable, HOS positive, in vitro capacitated/acrosome reacted spermatozoa and spermatozoa with intact acrosomes in pre-frozen and frozen-thawed semen of six cross bred bulls.
Most fluorescent dyes used to evaluate acrosome only provide information on its membrane integrity: probes only penetrate acrosomes with nonintact membranes.
Under the oil immersion lens, we found in partial globozoospermia not only a large number of acrosomeless sperm, but also lots of sperm with small acrosomes.
Additionally, ACRI values in cm presented a higher percentage than in cp, and those were greater than pm, similar to other reports in which the normal acrosomes percentage was higher in maternal line than in paternal lines (ROBINSON & BUHR, 2005; WYSOKINSKA & KONDRACKI, 2013).
Post thawed percentage of viable spermatozoa with intact acrosomes was higher (PLess than0.
17, 20) Our results showed that the LC administration led to a significant rise in the number of the sperms with intact acrosomes as demonstrated by PNA reaction.
It has been proposed that in some annelids and molluscs, elongated acrosomes have evolved in species that have protective membranes around the egg, or thicker egg envelopes (e.