Sperm

sperm cellspermatiasperm cellsspermatium sperm cells250cc's of George Sr.flagellated spermsperm nucleisperm sacspunk
Sperm is the male reproductive cell and is derived from the Greek word sperma (meaning "seed").wikipedia
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Anisogamy

anisogamous
In the types of sexual reproduction known as anisogamy and its subtype oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell.
(The related adjectives are anisogamous and anisogamic). The smaller gamete is considered to be male (sperm cell), whereas the larger gamete is regarded as female (egg cell).

Ploidy

diploidhaploid2n
The human sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell.
The number of chromosomes found in a single complete set of chromosomes is called the monoploid number (x). In most animals, the haploid number (n) is unique to gametes (sperm or egg cells), and refers to the total number of chromosomes found in a gamete, which under normal conditions is half the total number of chromosomes in a somatic cell.

Gamete

gametesgameticreproductive cells
In the types of sexual reproduction known as anisogamy and its subtype oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell.
In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual that produces the larger type of gamete—called an ovum (or egg)—and a male produces the smaller tadpole-like type—called a sperm.

Pronucleus

pronucleipronuclearsperm nucleus
The main sperm function is to reach the ovum and fuse with it to deliver two sub-cellular structures: (i) the male pronucleus that contains the genetic material and (ii) the centrioles that are structures that help organize the microtubule cytoskeleton.
A pronucleus (plural: pronuclei) is the nucleus of a sperm or an egg cell during the process of fertilization, after the sperm enters the ovum, but before the genetic material of the sperm and egg fuse.

Cervix

cervicalcervical mucuscervix uteri
The midpiece has a central filamentous core with many mitochondria spiralled around it, used for ATP production for the journey through the female cervix, uterus and uterine tubes.
The cervical canal is a passage through which sperm must travel to fertilize an egg cell after sexual intercourse.

Testicle

testestestistesticles
In mammals, sperm develops in the testicles, is stored in the epididymis, and released from the penis. The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division.
The functions of the testes are to produce both sperm and androgens, primarily testosterone.

Spermatozoon

spermatozoaspermsperm cells
A uniflagellar sperm cell that is motile is referred to as a spermatozoon, whereas a non-motile sperm cell is referred to as a spermatium. Sperm cells cannot divide and have a limited life span, but after fusion with egg cells during fertilization, a new organism begins developing, starting as a totipotent zygote.
A spermatozoon (pronounced, alternate spelling spermatozoön; plural spermatozoa; from "seed" and "living being") is a motile sperm cell, or moving form of the haploid cell that is the male gamete.

Spermatogenesis

spermatogenicsperm productionproduction of sperm
The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division.
These develop into mature spermatozoa, also known as sperm cells.

Zygote

zygoticzygotesfertilized egg
A uniflagellar sperm cell that is motile is referred to as a spermatozoon, whereas a non-motile sperm cell is referred to as a spermatium. Sperm cells cannot divide and have a limited life span, but after fusion with egg cells during fertilization, a new organism begins developing, starting as a totipotent zygote.
In human fertilization, a released ovum (a haploid secondary oocyte with replicate chromosome copies) and a haploid sperm cell (male gamete)—combine to form a single 2n diploid cell called the zygote.

Cell nucleus

nucleusnucleinuclear
head: contains the nucleus with densely coiled chromatin fibers, surrounded anteriorly by a thin, flattened sac called the acrosome, which contains enzymes used for penetrating the female egg. It also contains vacuoles.
Between 1877 and 1878, Oscar Hertwig published several studies on the fertilization of sea urchin eggs, showing that the nucleus of the sperm enters the oocyte and fuses with its nucleus.

Fertilisation

fertilizationconceptionfertilized
During fertilization, the sperm provides three essential parts to the oocyte: (1) a signalling or activating factor, which causes the metabolically dormant oocyte to activate; (2) the haploid paternal genome; (3) the centriole, which is responsible for forming the centrosome and microtubule system. Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization.
Double fertilisation is the process in angiosperms (flowering plants) in which two sperm from each pollen tube fertilise two cells in a female gametophyte (sometimes called an embryo sac) that is inside an ovule.

Gonad

gonadsgonadalreproductive glands
The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division.
In the female of the species the reproductive cells are the egg cells, and in the male the reproductive cells are the sperm.

Epididymis

epididymidesepididymalepididymectomy
In mammals, sperm develops in the testicles, is stored in the epididymis, and released from the penis.
Because sperm are initially non-motile as they leave the seminiferous tubules, large volumes of fluid are secreted to propel them to the epididymis.

Meiosis

meioticsyzygymeiosis I
The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division.
In some cases all four of the meiotic products form gametes such as sperm, spores, or pollen.

Ejaculation

ejaculateejaculatedejaculates
In addition to ejaculation, it is possible to extract sperm through TESE.
Ejaculation is the discharge of semen (normally containing sperm) from the male reproductory tract, usually accompanied by orgasm.

Semen

seminal fluidseminalsperm
Sperm cells are carried out of the male body in a fluid known as semen. Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization.
The normal environment of the vagina is a hostile one (c.f. sexual conflict) for sperm cells, as it is very acidic (from the native microflora producing lactic acid), viscous, and patrolled by immune cells.

Semen quality

sperm qualityqualitysperm viability
Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization.
In men with a normal level of sperm production (normozoospermia), the percentage of sperm DNA fragmentation is positively correlated with age, and inversely correlated with progressive sperm motility.

Centriole

centriolesciliogenesiscentric
The main sperm function is to reach the ovum and fuse with it to deliver two sub-cellular structures: (i) the male pronucleus that contains the genetic material and (ii) the centrioles that are structures that help organize the microtubule cytoskeleton. During fertilization, the sperm provides three essential parts to the oocyte: (1) a signalling or activating factor, which causes the metabolically dormant oocyte to activate; (2) the haploid paternal genome; (3) the centriole, which is responsible for forming the centrosome and microtubule system.
Sperm centrioles are important for 2 functions: (1) to form the sperm flagellum and sperm movement and (2) for the development of the embryo after fertilization.

Oogamy

oogamouslarge eggs
In the types of sexual reproduction known as anisogamy and its subtype oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell.
In some algae, most gymnosperms and all angiosperms, a variation of oogamy occurs where the sperm cells are non-motile as well.

Sperm bank

cryobankspermsperm banks
Some sperm banks hold up to 170 l of sperm.
Men who choose to donate semen through a sperm bank have the security of knowing that they are helping such women or childless couples to have children in circumstances where they, as the biological father, will not have any legal or other responsibility for the children produced from their sperm.

Spermatid

spermatidselongating spermatid
The spermatid stage is where the sperm develops the familiar tail.
As postmeiotic germ cells develop to mature sperm they progressively lose the ability to repair DNA damage that may then accumulate and be transmitted to the zygote and ultimately the embryo.

Antheridium

antheridiaantherozoidantherozoids
Sperm cells in algal and many plant gametophytes are produced in male gametangia (antheridia) via mitotic division.
An antheridium is a haploid structure or organ producing and containing male gametes (called antherozoids or sperm).

Pollen

exinepollen grainmicrosporogenesis
In flowering plants, sperm nuclei are produced inside pollen.
If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte.

Mitosis

mitoticmitosesmitotic division
Sperm cells in algal and many plant gametophytes are produced in male gametangia (antheridia) via mitotic division.
Important exceptions include the gametes – sperm and egg cells – which are produced by meiosis.

Oocyte

oocytesovocyteprimary oocyte
During fertilization, the sperm provides three essential parts to the oocyte: (1) a signalling or activating factor, which causes the metabolically dormant oocyte to activate; (2) the haploid paternal genome; (3) the centriole, which is responsible for forming the centrosome and microtubule system.
See anatomy of sperm