Spermatocyte
Encyclopedia
A spermatocyte is a male
gametocyte
, derived from a spermatogonium
, which is in the developmental stage of spermatogenesis
during which meiosis
occurs. It is located in the seminiferous tubules
of the testis.
to form primary spermatocytes. The primary spermatocyte is initially diploid and undergoes meiosis
. After the first meiotic division, the resulting daughter cells are termed secondary spermatocytes. These undergo the second meiotic division giving rise to haploid spermatids. Spermatids mature further in a developmental process called spermiogenesis
, becoming spermatozoa. Spermatozoa are characterized by an elongated shape with a compact nucleus
and a flagellum
. Additional maturation takes place in the epididymis
, although the sperm don't become motile until the addition of fructose to the ejaculate by the seminal vesicles. After capacitation
in the female reproductive tract, sperm are capable of fertilization.
Male
Male refers to the biological sex of an organism, or part of an organism, which produces small mobile gametes, called spermatozoa. Each spermatozoon can fuse with a larger female gamete or ovum, in the process of fertilization...
gametocyte
Gametocyte
A gametocyte is a eukaryotic germ cell that divides by mitosis into other gametocytes or by meiosis into gametids during gametogenesis. Male gametocytes are called spermatocytes, and female gametocytes are called oocytes....
, derived from a spermatogonium
Spermatogonium
A spermatogonium is an intermediary male gametogonium in the production of spermatozoa.There are three subtypes:...
, which is in the developmental stage of spermatogenesis
Spermatogenesis
Spermatogenesis is the process by which male primary germ cells undergo division, and produce a number of cells termed spermatogonia, from which the primary spermatocytes are derived. Each primary spermatocyte divides into two secondary spermatocytes, and each secondary spermatocyte into two...
during which meiosis
Meiosis
Meiosis is a special type of cell division necessary for sexual reproduction. The cells produced by meiosis are gametes or spores. The animals' gametes are called sperm and egg cells....
occurs. It is located in the seminiferous tubules
Seminiferous tubules
Seminiferous tubules are located in the testes, and are the specific location of meiosis, and the subsequent creation of gametes, namely spermatozoa....
of the testis.
Spermatogenesis
Spermatogenesis is the developmental process which leads to the production of male gametes, termed spermatozoa or sperm. Spermatogonial stem cells divide by mitosisMitosis
Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly...
to form primary spermatocytes. The primary spermatocyte is initially diploid and undergoes meiosis
Meiosis
Meiosis is a special type of cell division necessary for sexual reproduction. The cells produced by meiosis are gametes or spores. The animals' gametes are called sperm and egg cells....
. After the first meiotic division, the resulting daughter cells are termed secondary spermatocytes. These undergo the second meiotic division giving rise to haploid spermatids. Spermatids mature further in a developmental process called spermiogenesis
Spermiogenesis
Spermiogenesis is the final stage of spermatogenesis, which sees the maturation of spermatids into mature, motile spermatozoa. The spermatid is more or less circular cell containing a nucleus Golgi apparatus, centriole and mitochondria...
, becoming spermatozoa. Spermatozoa are characterized by an elongated shape with a compact nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
and a flagellum
Flagellum
A flagellum is a tail-like projection that protrudes from the cell body of certain prokaryotic and eukaryotic cells, and plays the dual role of locomotion and sense organ, being sensitive to chemicals and temperatures outside the cell. There are some notable differences between prokaryotic and...
. Additional maturation takes place in the epididymis
Epididymis
The epididymis is part of the male reproductive system and is present in all male amniotes. It is a narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens. A similar, but probably non-homologous, structure is found in cartilaginous...
, although the sperm don't become motile until the addition of fructose to the ejaculate by the seminal vesicles. After capacitation
Capacitation
Capacitation is the penultimate step in the maturation of mammalian spermatozoa and is required to render them competent to fertilize an oocyte.This step is a biochemical event; the sperm move normally and look mature prior to capacitation....
in the female reproductive tract, sperm are capable of fertilization.