acrosomal granule

granule /gran·ule/ (gran´ūl)

1. a small particle or grain.

2. a small pill made from sucrose.

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acidophil granules  granules staining with acid dyes.

acrosomal granule  a large globule contained within a membrane-bounded acrosomal vesicle, which enlarges further to become the core of the acrosome of a spermatozoon.

alpha granules 

1. oval granules found in blood platelets; they are lysosomes containing acid phosphatase.

2. large granules in the alpha cells of the islets of Langerhans; they secrete glucagon.

3. granules found in the acidophils of the adenohypophysis.

azurophil granule  one staining easily with azure dyes; they are coarse reddish granules seen in many lymphocytes.

basal granule  see under body.

basophil granule 

1. any granule staining with basic dyes.

2. one of the coarse bluish-black granules found in basophils.

3. (pl.) beta g's (2).

beta granules 

1. granules in the beta cells of the islets of Langerhans; they secrete insulin.

2. granules found in the basophils of the adenohypophysis.

Birbeck granules  membrane-bound rod- or tennis racquet–shaped structures with a central linear density, found in the cytoplasm of Langerhans' cells.

chromaffin granules  organelles in the chromaffin cells of the adrenal medulla, where epinephrine and norepinephrine are synthesized, stored, and released.

elementary granules  hemoconia.

eosinophil granule  one of the coarse round granules that stain with eosin and are found in eosinophils.

iodophil granules  granules staining brown with iodine, seen in polymorphonuclear leukocytes in various acute infectious diseases.

keratohyalin granules  irregularly shaped granules, representing deposits of keratohyalin on tonofibrils in the stratum granulosum of the epidermis.

lamellar granule  keratinosome.

Langerhans granules  Birbeck g's.

membrane-coating granule  keratinosome.

metachromatic granule  a granular cell inclusion present in many bacterial cells, having an avidity for basic dyes and causing irregular staining of the cell.

Nissl's granules  see under body.

oxyphil granules  acidophil g's.

pigment granules  small masses of coloring matter in pigment cells.

proacrosomal granule  one of the small, dense bodies found inside one of the vacuoles of the Golgi body, which fuse to form an acrosomal granule.

Schüffner's granules  see under dot.

seminal granules  the small granular bodies in the spermatic fluid.

specific atrial granules  membrane-bound spherical granules with a dense homogeneous interior that are concentrated in the core of sarcoplasm of the atrial cardiac muscle, extending in either direction from the poles of the nucleus, usually near the Golgi complex; they are the storage site of atrial natriuretic peptide.

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acrosomal granule

n.

A large granule that is formed by the coalescing of proacrosomal granules within the acrosomal vesicle and adheres to the nuclear envelope of a developing spermatozoon.