acrosome

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Related to Acrosomes: Acrosome reaction, Acrosomal process

acrosome

 [ak´ro-sōm]
the caplike, membrane-bound structure covering the anterior portion of the head of a spermatozoon; it contains enzymes involved in penetration of the ovum.
Acrosome of a spermatozoon. From Applegate, 2000.
acrosome reaction changes in the spermatozoon that result in development of perforations in the acrosome, allowing release of enzymes that facilitate fertilization.

ac·ro·some

(ak'rō-sōm),
A caplike organelle or saccule derived from Golgi elements that surround the anterior two thirds of the nucleus of a sperm. Enzymes contained within this structure probably facilitate the sperm's penetration of the zona pellucida of the oocyte.
Synonym(s): acrosomal cap, head cap
[acro- + G. soma, body]

acrosome

/ac·ro·some/ (ak´ro-sōm) the caplike, membrane-bound structure covering the anterior portion of the head of a spermatozoon; it contains enzymes for penetrating the oocyte.

acrosome

(ăk′rə-sōm′)
n.
A caplike structure at the anterior end of a spermatozoon that produces enzymes aiding in egg penetration.

ac′ro·so′mal (-sō′məl) adj.

acrosome

[ak′rəsōm′]
Etymology: Gk, akron + soma, body
the caplike structure surrounding the anterior end of the head of a spermatozoon. It is derived from the Golgi apparatus within the cytoplasm and contains degradative enzymes that function in the penetration of the ovum during fertilization. Also called acrosomal cap, acrosomal head cap. See also acrosomal reaction. acrosomal, adj.

Acrosome

A membrane-bound cap-like structure at the head of a spermatozoon that contains lytic enzymes—e.g., acrosin hyaluronidase—which degrade the ovum’s zona pellucida, allowing the penetration of one sperm.

acrosome

Reproduction biology A membrane-bound cap-like structure at the head of a spermatozoon that contains lytic enzymes–acrosin hyaluronidase which degrade the outer coat of the egg and allow the penetration of one sperm. See Acrosome reaction. Cf Capacitation.

ac·ro·some

(ak'rō-sōm)
A caplike organelle that surrounds the anterior two thirds of the nucleus of a sperm. Within this cap are enzymes that are thought to facilitate entry of the sperm into the oocyte.
[acro- + G. soma, body]

acrosome

A tiny sac or double membrane in the head of a SPERMATOZOON that contains the digestive enzymes needed to break down the protective cell membrane of the egg (OVUM) and allow penetration. Release of these enzymes is called the acrosome reaction.
Acrosomeclick for a larger image
Fig. 8 Acrosome . Head of a typical mammalian sperm.

acrosome

a membrane-bound sac derived from the GOLGI APPARATUS, located at the tip of the sperm. The acrosome plays an important role in fertilization. It contains enzymes that, when the sac ruptures upon contact with the egg, aid in penetration of the egg membrane, so allowing transfer of the sperm nucleus to the egg cell. See Fig. 8 .

acrosome

the caplike, membrane-bounded structure that covers the anterior portion of the head of the mammalian spermatozoon; it is bounded by an inner and an outer membrane and contains enzymes involved in penetration of the ovum.

acrosome reaction
fusion of the outer acrosomal membrane with the sperm plasma membrane, and the breakdown of the fused complex, after the attachment of the spermatozoon to the zona pellucida. It is induced by substances from the egg investments and releases enzymes involved in penetration of the ovum.
References in periodicals archive ?
To determine the reason behind the penetration defect of sperm from boar 2012, acrosome formation was analyzed using Pisum sativum agglutinin (PSA) staining.
The present finding was in agreement to these reports as the percentage of ram spermatozoa with normal acrosome decreased significantly during incubation (15).
The acrosome may be absent or abnormal and the head may be amorphous, tapering, pyriform, double, or have a flat side/base.
Analysis of acrosome condition in hormone-supplemented treatments: Acrosome condition was analyzed using the improved Coomassie Brilliant Blue (Bio-Rad, CA, USA) method described by de Leeuw et al.
0 mM) on the motility, progressive motility, viability, membranes (hypoosmotic swelling test) and acrosome integrity after dilution (first part of experiment) of ram spermatozoa.
The Fine Structure of the Acrosome Shows the Phylogenetic Relationship Between Decapod Species
The destruction of acrosome membrane may induce this phenomenon.
Regulation of abalone sperm cyclic AMP concentration and the acrosome reaction by calcium and methylxanthines.
Normal acrosomes were assessed by viewing wet mounts of diluted spermatozoa fixed in buffered Formalin-Citrate solution (Weitze, 1977).
Various methods have been employed for the evaluation of motility, acrosome integrity, sperm viability and sperm ATP concentration.
Acrosomes were differentially categorized into four morphological classes: normal apical ridge (NAR), damaged apical ridge (DAR), missing apical ridge (MAR) and loose acrosomal cap (LAC) as described by Pursel et al.