acrosome

[ ak-ruh-sohm ]

noun

, Cell Biology.

1. 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.

acrosome

/ ˈækrəˌsəʊm /

noun

1. 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

Other Words From

• acro·somal adjective

Word History and Origins

Origin of acrosome¹

1895–1900; < German Akrosoma; acro-, -some ³

Word History and Origins

Origin of acrosome¹

C19: from acro- + -some ³

Example Sentences

Spermatids containing both the chromatin nucleolus (n) and the odd chromosome (x), a the acrosome.

From Project Gutenberg

Spermatid, showing acrosome material (a) migrating to side of nucleus opposite centrosome.

From Project Gutenberg

The acrosome seems to develop directly out of the cytoplasm.

From Project Gutenberg