Spermatozoa
A spermatozoon (; also spelled spermatozoön; ; ) is a motile sperm cell (biology), cell, or moving form of the ploidy, haploid cell (biology), cell that is the male gamete. A spermatozoon Fertilization, joins an ovum to form a zygote. (A zygote ...
develop in the
seminiferous tubules of the testes. During their development the
spermatogonia
A spermatogonium (plural: ''spermatogonia'') is an undifferentiated male germ cell. Spermatogonia undergo spermatogenesis to form mature spermatozoa in the seminiferous tubules of the testis.
There are three subtypes of spermatogonia in humans: ...
proceed through
meiosis
Meiosis (; , since it is a reductional division) is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells. It involves two rounds of division that ultimately ...
to become spermatozoa. Many changes occur during this process: the DNA in nuclei becomes condensed; the
acrosome develops as a structure close to the nucleus. The acrosome is derived from the
Golgi apparatus
The Golgi apparatus (), also known as the Golgi complex, Golgi body, or simply the Golgi, is an organelle found in most eukaryotic cells. Part of the endomembrane system in the cytoplasm, it packages proteins into membrane-bound vesicles ...
and contains hydrolytic enzymes important for fusion of the spermatozoon with an
egg cell
The egg cell, or ovum (plural ova), is the female reproductive cell, or gamete, in most anisogamous organisms (organisms that reproduce sexually with a larger, female gamete and a smaller, male one). The term is used when the female gamete is ...
. During spermiogenesis the nucleus condenses and changes shape. Abnormal shape change is a feature of sperm in
male infertility.
The acroplaxome is a structure found between the acrosomal membrane and the
nuclear membrane.
The acroplaxome contains structural proteins including keratin 5,
F-actin[ and profilin IV.]
References
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Cell biology