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The term sperm is derived from the Greek word (sp??ľa) sperma (meaning "seed") and refers to the male reproductive cells
Cell (biology)

The cell is the structural and functional unit of all known Life organisms. It is the smallest unit of an organism that is classified as living, and is often called the building bricks of life....
. In the types of sexual reproduction
Sexual reproduction

Sexual reproduction is characterized by processes that pass a Genetic recombination of Genetics material to offspring, resulting in Genetic diversity....
 known as anisogamy
Anisogamy

Anisogamy refers to a form of sexual reproduction involving gametes of different sizes. The smaller gamete is considered to be male whereas the larger gamete is regarded as female ....
 and oogamy
Oogamy

Oogamy is a form of anisogamy in which the female gamete is significantly larger than the male gamete and is non-motile. The male gametes are typically highly motile spermatozoon competing for the fertilization of the immotile egg....
, there is a marked difference in the size of the gamete
Gamete

A gamete is a Cell that fuses with another gamete during fertilization in organisms that sexual reproduction. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete?called an ovum ?and a male produces th...
s with the smaller one being termed the "male" or sperm cell.






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Sperm Egg
The term sperm is derived from the Greek word (sp??ľa) sperma (meaning "seed") and refers to the male reproductive cells
Cell (biology)

The cell is the structural and functional unit of all known Life organisms. It is the smallest unit of an organism that is classified as living, and is often called the building bricks of life....
. In the types of sexual reproduction
Sexual reproduction

Sexual reproduction is characterized by processes that pass a Genetic recombination of Genetics material to offspring, resulting in Genetic diversity....
 known as anisogamy
Anisogamy

Anisogamy refers to a form of sexual reproduction involving gametes of different sizes. The smaller gamete is considered to be male whereas the larger gamete is regarded as female ....
 and oogamy
Oogamy

Oogamy is a form of anisogamy in which the female gamete is significantly larger than the male gamete and is non-motile. The male gametes are typically highly motile spermatozoon competing for the fertilization of the immotile egg....
, there is a marked difference in the size of the gamete
Gamete

A gamete is a Cell that fuses with another gamete during fertilization in organisms that sexual reproduction. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete?called an ovum ?and a male produces th...
s with the smaller one being termed the "male" or sperm cell. The human
Human

A human being, also human or man, is a member of a species of bipedalism primates in the family Hominidae . Mitochondrial DNA evidence indicates that modern humans originated in east Africa about 200,000 years ago....
 sperm cell is haploid, so that its 23 chromosomes can join the 23 chromosomes of the female egg to form a diploid cell. A uniflagellar sperm cell that is motile
Motility

Motility is a biology term which refers to the ability to move spontaneously and actively, consuming energy in the process. It can apply to either single-celled or multicellular organisms....
 is referred to as a spermatozoon
Spermatozoon

A sperm, from the ancient Greek word sp???a and and more commonly known as a sperm cell, is the ploidy cell that is the male gamete. It Fertilization an ovum to form a zygote....
, 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
Ovum

An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization....
 during fertilization, a totipotent
Totipotency

Totipotency is the ability of a single cell to divide and produce all the differentiated cells in an organism, including extraembryonic tissues....
 zygote
Zygote

A zygote is a cell that is the result of fertilization. That is, two ploidy cells—usually an ovum from a female and a sperm cell from a male—merge into a single ploidy cell called the zygote ....
 is formed with the potential to develop into a new organism. Mammalian sperm cells can live for up to 3 days inside the female reproductive system. The spermatozoa of animal
Animal

Animals are a major group of multicellular, eukaryotic organisms of the Kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life....
s are produced through spermatogenesis
Spermatogenesis

Spermatogenesis is the process by which male spermatogonia develop into mature spermatozoa. Spermatozoa are the mature male gametes in many sexually reproducing organisms....
 inside the male gonad
Gonad

The gonad is the organ that makes gametes. The gonads in males are the testes and the gonads in females are the ovaries. The product, gametes, are haploid germ cells....
s (testicle
Testicle

The testicle is the male gonad in animals. This article will concentrate on mammalian testicles unless otherwise noted.The etymology of the word is somewhat colorfully based on Roman law....
s) via meiotic
Meiosis

In biology or life science, meiosis is a process of reductional division in which the number of chromosomes per cell is halved. In animals, meiosis always results in the formation of gametes, while in other organisms it can give rise to spores....
 division. Sperm cells in algal and many plant gametophyte
Gametophyte

In plants and algae that undergo alternation of generations, a gametophyte is the multicellular structure, or phase, that is haploid, containing a single set of chromosomes:...
s are produced in male gametangia (antheridia
Antheridium

An antheridium is a haploid structure or organ producing and containing male gametes . It is present in the gametophyte phase of lower plants like mosses and ferns, and also in the primitive vascular Psilotophyta....
) via mitotic
Mitosis

Mitosis is the process in which a eukaryotic cell separates the chromosomes in its cell nucleus, into two identical sets in two daughter nuclei....
 division. In flowering plant
Flowering plant

The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
s, sperm nuclei are produced inside pollen
Pollen

Pollen is a fine to coarse powder consisting of Gametophyte , which produce the male gametes of spermatophyta. A hard coat covering the pollen grain protects the sperm cells during the process of their movement between the stamens of the flower to the pistil of the next flower....
.

Anatomy


The sperm cell consists of a head, a midpiece and a tail. The head contains the nucleus
Cell nucleus

In cell biology, the nucleus , also sometimes referred to as the "control center", is a membrane-enclosed organelle found in all eukaryote cell ....
 with densely coiled chromatin fibres, surrounded anteriorly by an acrosome
Acrosome

In spermatozoon of many animals, the Acrosome is an organelle that develops over the anterior half of the sperm's head. It is a cap-like structure derived from the Golgi apparatus....
, which contains enzymes used for penetrating the female egg. The midpiece has a central filamentous core with many mitochondria spiralled around it, used for ATP
ATP

ATP may refer to:...
 production for the journey through the female cervix
Cervix

The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall....
, uterus
Uterus

The uterus is a major female hormone-responsive reproductive sex organ of most mammals, including humans. It is within the uterus that the fetus develops during gestation....
 and uterine tubes. The tail or "flagellum
Flagellum

A flagellum is a tail-like structure that projects from the cell body of certain prokaryotic and eukaryotic cells, and it functions in locomotion....
" executes the lashing movements that propel the spermatocyte.

Motile sperm cells

Motile sperm cells typically move via flagella
Flagellum

A flagellum is a tail-like structure that projects from the cell body of certain prokaryotic and eukaryotic cells, and it functions in locomotion....
 and require water in order to swim toward the egg for fertilization. The uniflagellated sperm cells (with one flagellum) produced in most animal
Animal

Animals are a major group of multicellular, eukaryotic organisms of the Kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life....
s are referred to as spermatozoa
Spermatozoon

A sperm, from the ancient Greek word sp???a and and more commonly known as a sperm cell, is the ploidy cell that is the male gamete. It Fertilization an ovum to form a zygote....
, and are known to vary in size.

Motile sperm are also produced by many protist
Protist

Protists ; eukaryote microorganisms. Historically, protists were treated as the kingdom Protista but this group is no longer recognized in modern taxonomy....
s and the gametophyte
Gametophyte

In plants and algae that undergo alternation of generations, a gametophyte is the multicellular structure, or phase, that is haploid, containing a single set of chromosomes:...
s of bryophyte
Bryophyte

Bryophytes are all embryophytes that are non-vascular plant: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids....
s, fern
Fern

A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta....
s and some gymnosperm
Gymnosperm

Gymnosperm is a group of spermatophyte seed-bearing plants with ovules on scales, which are usually arranged in cone-like structures. The other major group of seed-bearing plants, the angiosperms, [from the Greek, 'angion' - container] have ovules enclosed in a carpel, a sporophyll with fused margins....
s such as cycad
Cycad

File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
s and ginkgo
Ginkgo

Ginkgo , frequently misspelled as "Gingko", and also known as the Maidenhair Tree after Adiantum, is a unique species of tree with no close living relatives....
. The sperm cells are the only flagellated cells in the life cycle of these plants. In many ferns and lycophytes, they are multi-flagellated (carrying more than one flagellum).

In nematode
Nematode

The "roundworms" or "nematodes" are the most diverse phylum of body cavity, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 80,000 have been described, of which over 15,000 are parasite....
s, the sperm cells are amoeboid
Amoeboid

Amoeboids are unicellular life-forms characterized by their similarity to amoebas....
 and crawl, rather than swim, towards the egg cell.

In order to move towards the ova the sperm swim through the womans vaginal juices coating the walls of the womb and cervix.

Non-motile sperm cells

Non-motile sperm cells called spermatia lack flagella and therefore cannot swim. Spermatia are produced in a spermatangium.

Because spermatia cannot swim,they depend on their environment to carry them to the egg cell. Some red algae, such as Polysiphonia
Polysiphonia

Polysiphonia is a genus of red algae with about 19 species on the coasts of the British Isles  and about 200 species world-wide, including Antarctica and Greenland.  It is in the Order Ceramiales and Family Rhodomelaceae. ...
, produce non-motile spermatia that are spread by water currents after their release. The spermatia of rust fungi
Rust (fungus)

Rusts are fungi of the order Uredinales. Many of these species are plant parasites. Some are superficially similar to the smut , although their relation to each other is not clear....
 are covered with a sticky substance. They are produced in flask-shaped structures containing nectar, which attract flies
Fly

True flies are insects of the Order Diptera , possessing a single pair of insect wing on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax....
 that transfer the spermatia to nearby hyphae for fertilization in a mechanism similar to insect pollination in flowering plant
Flowering plant

The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
s.

Fungal spermatia (also called pycnidiospores) may be confused with conidia
Conidium

Conidia, sometimes termed conidiospores, are Asexual reproduction, non-motile spores of a fungus; they are also called mitospores due to the way they are generated through the cellular process of mitosis....
. Conidia are spore
Spore

In biology, a spore is a reproduction structure that is adapted for biological dispersal and surviving for extended periods of time in unfavorable conditions....
s that germinate independently of fertilization, whereas spermatia are gamete
Gamete

A gamete is a Cell that fuses with another gamete during fertilization in organisms that sexual reproduction. In species which produce two morphologically distinct types of gametes, and in which each individual produces only one type, a female is any individual which produces the larger type of gamete?called an ovum ?and a male produces th...
s that are required for fertilization. In some fungi, such as Neurospora crassa
Neurospora crassa

Neurospora crassa is a type of red bread mold of the phylum Ascomycota. The genus name, meaning "nerve spore" refers to the characteristic striations on the spores....
, spermatia are identical with microconidia as they can perform both functions of fertilization as well as giving rise to new organisms without fertilization.

Sperm nuclei

In many land plants, including most gymnosperms and all angiosperms, the male gametophyte
Gametophyte

In plants and algae that undergo alternation of generations, a gametophyte is the multicellular structure, or phase, that is haploid, containing a single set of chromosomes:...
s (pollen grains
Pollen

Pollen is a fine to coarse powder consisting of Gametophyte , which produce the male gametes of spermatophyta. A hard coat covering the pollen grain protects the sperm cells during the process of their movement between the stamens of the flower to the pistil of the next flower....
) are the primary mode of dispersal
Biological dispersal

Biological dispersal refers to a species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population genetics, and species distribution....
, for example via wind or insect pollination
Pollination

Pollination in flowering plants and gymnosperms is the process that transfers pollen, which contain the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself....
, eliminating the need for water to bridge the gap between male and female. Each pollen grain contains a spermatogenous (generative) cell. Once the pollen lands on the stigma of a receptive flower, it germinates and starts growing a pollen tube
Pollen tube

The pollen tube of most seed plants acts as a conduit to transport sperm cells from the pollen grain, either from the stigma to the ovules at the base of the pistil, or directly through ovule tissue in some gymnosperms ....
 through the carpel. Before the tube reaches the ovule
Ovule

Ovule literally means "small ovum." In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integuments forming its outer layer, the nucellus , and the megaspore-derived female gametophyte in its center....
, the nucleus of the generative cell in the pollen grain divides and gives rise to two sperm nuclei which are then discharged through the tube into the ovule
Ovule

Ovule literally means "small ovum." In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: The integuments forming its outer layer, the nucellus , and the megaspore-derived female gametophyte in its center....
 for fertilization.

In some protist
Protist

Protists ; eukaryote microorganisms. Historically, protists were treated as the kingdom Protista but this group is no longer recognized in modern taxonomy....
s, fertilization also involves sperm nuclei
Cell nucleus

In cell biology, the nucleus , also sometimes referred to as the "control center", is a membrane-enclosed organelle found in all eukaryote cell ....
, rather than cells, migrating toward the egg cell through a fertilization tube. Oomycetes form sperm nuclei in a syncytical
Syncytium

In biology, a syncytium is a large cell-like structure filled with cytoplasm containing many cell nucleus....
 antheridium
Antheridium

An antheridium is a haploid structure or organ producing and containing male gametes . It is present in the gametophyte phase of lower plants like mosses and ferns, and also in the primitive vascular Psilotophyta....
 surrounding the egg cells. The sperm nuclei reach the eggs through fertilization tubes, similar to the pollen tube mechanism in plants.

Sperm quality

A study by the University of California
University of California

The University of California is a public university system in the U.S. state of California. Under the California Master Plan for Higher Education, the University of California is a part of the state's three-tier public higher education system, which also includes the California State University system and the California Community Colleges s...
 has suggested that folate may protect sperm cells from aneuploidy
Aneuploidy

Aneuploidy is defined as an abnormal number of chromosomes. Syndromes caused by an extra or missing chromosome are among the most widely recognized genetic disorders in humans....
.

Market

On the global market, Denmark
Denmark

Denmark is a Scandinavian country in northern Europe and the senior member of the Kingdom of Denmark. It is the southernmost of the Nordic countries....
 has a well developed system of sperm export. This success mainly comes from the reputation of Danish sperm donors for being of high quality and, in contrast with the law in the other Nordic countries, gives donors the choice of being either anonymous or non-anonymous to the receiving couple. Furthermore, Nordic sperm donors tend to be tall and highly educated and have altruistic motives for their donations, partly due to the relatively low monetary compensation in Nordic countries. More than 50 countries worldwide are importers of Danish sperm, including Paraguay
Paraguay

Paraguay, officially the Republic of Paraguay , is one of the only two landlocked countries in South America . It lies on both banks of the Paraguay River and is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest....
, Canada
Canada

Canada is a country occupying most of northern North America, extending from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean....
, Kenya
Kenya

The Republic of Kenya is a country in East Africa. It is bordered by Ethiopia to the north, Somalia to the northeast, Tanzania to the south, Uganda to the west, and Sudan to the northwest, with the Indian Ocean running along the southeast border....
, and Hong Kong
Hong Kong

Hong Kong , officially the Hong Kong Special Administrative Region, is a territory located in Southern China in East Asia, bordering the province of Guangdong to the north and facing the South China Sea to the east, west and south....
. However, the Food and Drug Administration
Food and Drug Administration

The U.S. Food and Drug Administration is an Government agency of the United States Department of Health and Human Services and is responsible for regulating and supervising the safety of foods, dietary supplements, Medications, vaccines, Biopharmaceutical, blood transfusion, medical devices, Electromagnetic radiation-emitting devices, veteri...
 (FDA) of the US has banned import of any sperm, motivated by a risk of mad cow disease
Creutzfeldt-Jakob disease

Creutzfeldt–Jakob disease is a very rare and incurable degeneration neurology that is fatal. Among the types of transmissible spongiform encephalopathy found in humans, it is the most common....
, although such a risk is insignificant, since artificial insemination is very different from the route of transmission of mad cow disease
Creutzfeldt-Jakob disease

Creutzfeldt–Jakob disease is a very rare and incurable degeneration neurology that is fatal. Among the types of transmissible spongiform encephalopathy found in humans, it is the most common....
. The prevalence of mad cow disease
Creutzfeldt-Jakob disease

Creutzfeldt–Jakob disease is a very rare and incurable degeneration neurology that is fatal. Among the types of transmissible spongiform encephalopathy found in humans, it is the most common....
 is one in a million, probably less for donors. If prevalence was the case, the infectious proteins would then have to cross the blood-testis barrier
Blood-testis barrier

The blood-testis barrier is a physical barrier between the blood vessels and the seminiferous tubules of the animal testicle.The barrier is formed by tight connections between the Sertoli cells, which are sustentacular cells of the seminiferous tubules, and nourish the Spermatogonium....
 to make transmission possible. Transmission of the disease by an insemination is approximately equal to the risk of getting killed by lightning.

Great Britain
Great Britain

Great Britain is an island lying to the northwest of Continental Europe. It is the List of islands by area, and the largest in Europe. With a population of 58.9 million people it is List of islands by population....
, on the other hand, as well as Sweden, has a sperm shortage, due to ban of anonymous sperm donation.

See also

  • Ejaculation
    Ejaculation

    Ejaculation is the ejecting of semen from the penis, and is usually accompanied by orgasm. It is usually the result of sexual stimulation. Rarely, it is due to prostatic disease....
  • Female sperm
    Female sperm

    Female sperm is a term that traditionally refers to a sperm that contains an X chromosome produced, in the usual way by a male. However, for over 20 years, dating back to the late 1980s, scientists have explored how to produce sperm where all of the chromosomes come from an adult woman....
  • Polyspermy
    Polyspermy

    In biology, polyspermy describes an Ovum that has been Fertilisation by more than one Spermatozoon. Ploidy organisms normally contain two copies of each chromosome, one from each parent....
  • Semen
    Semen

    Semen is an organic fluid, also known as seminal fluid, that usually contains spermatozoon....
  • Sperm competition
    Sperm competition

    Sperm competition is "competition between sperm of two or more males for the fertilization of an ovum". Sperm competition is often compared to having tickets in a raffle; a male has a better chance of winning the more tickets he has ....
  • Sperm donation
    Sperm donation

    Sperm donation is the name of the provision by a man, known as a sperm donor, of his semen with the intention that it be used to achieve a pregnancy and produce a baby in a woman who is not the man's sexual partner and with whom the man does not have sexual intercourse....