FACTOID # 23: Wisconsin has more metal fabricators per capita than any other state.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
 
WHAT'S NEW
RELATED ARTICLES
People who viewed "Sperm" also viewed:
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Sperm
Different types of sperm cells: A) spermatozoon (motile), B) spermatium (non-motile), C) fertilization tube with sperm nuclei
Different types of sperm cells: A) spermatozoon (motile), B) spermatium (non-motile), C) fertilization tube with sperm nuclei

The term sperm is derived from the Greek word (σπέρμα) sperma (meaning "seed") and refers to the male reproductive cells. Sperm cells are the smaller gametes involved in fertilization in anisogamy and oogamy. In these types of sexual reproduction, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell. The human sperm cell is a 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 is also referred to as spermatozoon, whereas a non-motile sperm cell is referred to as spermatium. Sperm cells cannot divide and have a limited life span, but they can fuse with egg cells during fertilization to form a totipotent zygote with the potential to develop into a new organism. Mammalian sperm cells can live for up to 3 days inside the female unless it is exposed to air or is mixed with another liquid.[citation needed] The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) through meiosis. Sperm cells in algal and many plant gametophytes are produced in male gametangia (antheridia) through mitosis. In flowering plants, sperm nuclei are produced inside pollen. A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ... Motility is a biological term which refers to the ability to move spontaneously and independently. ... A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... Categories: Biology stubs ... Gametes (in Greek: γαμέτες) —also known as sex cells, or spores—are the specialized germ cells that come together during fertilization (conception) in organisms that reproduce sexually. ... Oogamy is a form of heterogamy in which the female produced gamete is signifcantly larger than the male gamete. ... Sexual reproduction is characterized by processes that pass a combination of genetic material to offspring, resulting in diversity. ... Haploid (meaning simple in Greek) cells have only one copy of each chromosome. ... Diploid (meaning double in Greek) cells have two copies (homologs) of each chromosome (both sex- and non-sex determining chromosomes), usually one from the mother and one from the father. ... Motility is a biological term which refers to the ability to move spontaneously and independently. ... A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ... A human ovum Sperm cells attempting to fertilize an ovum An ovum (plural ova) is a haploid female reproductive cell or gamete. ... Totipotency is the ability of a single cell, usually a stem cell, to divide and produce all the differentiated cells in an organism, including extraembryonic tissues. ... For other meanings see Zygote (disambiguation). ... Cross section of the epithelium of a seminiferous tubule showing various stages of spermatocyte development Spermatogenesis is the process by which male spermatogonia develop into mature spermatozoa. ... The gonad is the organ that makes gametes. ... Look up testes in Wiktionary, the free dictionary. ... For the figure of speech, see meiosis (figure of speech). ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... A gametangium (plural: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. ... Diagram of antheridium anatomy An antheridium (plural: antheridia) is a structure or organ of the gametophyte phase of certain plants producing and containing the spermatids or male gametes. ... Mitosis divides genetic information during cell division. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ...

Contents

Anatomy

The sperm cell consists of a head, a midpiece and a tail. The head is the nucleus with densely coiled cromatinfibres, surrounded anteriorly by an acrosome, 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 production for the journey through the female cervix, uterus and uterine tubes. The tail or "flagellum" executes the lashing movements that propel the spermatocyte, and it consists of microtubules in an extension of the cell membrane. Look up nucleus in Wiktionary, the free dictionary. ... In spermatozoa of many animals, the acrosome is an organelle that develops over the anterior half of the spermatozoons head. ... The cervix (from Latin neck) is the lower, narrow portion of the uterus where it joins with the top end of the vagina. ... This article is about female reproductive anatomy. ... Female internal reproductive anatomy The Fallopian tubes, also known as oviducts, uterine tubes, and salpinges (singular salpinx), are two very fine tubes leading from the ovaries of female mammals into the uterus. ... For the insect anatomical structure, see Antenna (biology). ...


Motile sperm cells

Motile sperm cells of algae and seedless plants.[1]

Motile sperm cells typically move via flagella and require water in order to swim toward the egg for fertilization. The uniflagellated sperm cells (with one flagellum) produced in most animals are referred to as spermatozoa, and are known to vary in size. Image File history File links Size of this preview: 300 × 600 pixelsFull resolution (301 × 602 pixel, file size: 31 KB, MIME type: image/png) Motile plant and algae sperm cells. ... Image File history File links Size of this preview: 300 × 600 pixelsFull resolution (301 × 602 pixel, file size: 31 KB, MIME type: image/png) Motile plant and algae sperm cells. ... For the insect anatomical structure, see Antenna (biology). ... For other uses, see Animal (disambiguation). ... A spermatozoon or spermatozoan ( spermatozoa), from the ancient Greek σπέρμα (seed) and (living being) and more commonly known as a sperm cell, is the haploid cell that is the male gamete. ...


Motile sperm are also produced by many protists and the gametophytes of bryophytes, ferns and some gymnosperms such as cycads and ginkgo. 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).[1] Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... The bryophytes are those embryophytes (land plants) that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. ... This article is about the group of pteridophyte plants. ... Divisions Pinophyta (or Coniferophyta) - Conifers Ginkgophyta - Ginkgo Cycadophyta - Cycads Gnetophyta - Gnetum, Ephedra, Welwitschia Gymnosperm (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, which are usually arranged in cone-like structures. ... Families Cycadaceae cycas family Stangeriaceae stangeria family Zamiaceae zamia family Leaves and male cone of Cycas revoluta Cycads are an ancient group of seed plants characterized by a large crown of compound leaves and a stout trunk. ... Species G. biloba L. The Ginkgo (Ginkgo biloba; 銀杏 in Chinese), frequently misspelled as Gingko, and also known as the Maidenhair Tree, is a unique tree with no close living relatives. ... Classes Lycopodiopsida - clubmosses Selaginellopsida - spikemosses Isoetopsida - quillworts The division Lycopodiophyta is a tracheophyte subdivision of the Kingdom Plantae that includes some of the most primitive of extant (living) vascular plants. ...


In nematodes, the sperm cells are amoeboid and crawl, rather than swim, towards the egg cell.[2] Classes Adenophorea    Subclass Enoplia    Subclass Chromadoria Secernentea    Subclass Rhabditia    Subclass Spiruria    Subclass Diplogasteria    Subclass Tylenchia The nematodes or roundworms (Phylum nematoda from Greek (nema): thread + -ode like) are one of the most common phyla of animals, with over 80,000 different described species (over 15,000 are parasitic). ... Amoeba (Chaos diffluens) Foraminiferan (Ammonia tepida) Heliozoan (Actinophrys sol) Amoeboids are cells that move or feed by means of temporary projections, called pseudopods (false feet). ...


Non-motile sperm cells

Non-motile sperm cells called spermatia lack flagella and therefore cannot swim. Spermatia are produced in a spermatangium.[1] A gametangium (plural: gametangia) is an organ or cell in which gametes are produced that is found in many multicellular protists, algae, fungi, and the gametophytes of plants. ...


Because spermatia cannot swim,they depend on their environment to carry them to the egg cell. Some red algae, such as Polysiphonia, produce non-motile spermatia that are spread by water currents after their release.[1] The spermatia of rust fungi are covered with a sticky substance. They are produced in flask-shaped structures containing nectar, which attract flies that transfer the spermatia to nearby hyphae for fertilization in a mechanism similar to insect pollination in flowering plants.[3] Possible classes Florideophyceae Bangiophyceae Cyanidiophyceae Red algae (Rhodophyta, pronounced /ˈrəʊdÉ™(ÊŠ)ËŒfʌɪtÉ™/) are a large group of mostly multicellular, marine algae, including many notable seaweeds. ... Polysiphonia is a genus of red algae with about 19 species on the coasts of the British Isles [1], and about 200 species world-wide, including Antarctica and Greenland [2][3]. It is in the Order Ceramiales and Family Rhodomelaceae [4]. // Polysiphonia is a red alga, filamentous and usually well... Families Pucciniaceae Melampsoraceae Coleosporiaceae Cronartiaceae Phragmidiaceae Pucciniastraceae Rusts are fungi of the order Uredinales. ... In Greek mythology, nectar and ambrosia are the food of the gods. ... For other uses, see Fly (disambiguation) and Flies (disambiguation). ... A hypha (plural hyphae) is a long, branching filament that, with other hyphae, forms the feeding thallus of a fungus called the mycelium. ... Closeup of a bee pollinating a flower Entomophily is a form of pollination whereby pollen is distributed by insects, particularly bees, Lepidoptera (e. ... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants or angiosperms are the most widespread group of land plants. ...


Fungal spermatia (also called pycnidiospores) may be confused with conidia. Conidia are spores that germinate independently of fertilization, whereas spermatia are gametes that are required for fertilization. In some fungi, such as Neurospora crassa, spermatia are identical with microconidia as they can perform both functions of fertilization as well as giving rise to new organisms without fertilization.[4] Conidia Conidia are asexual spores of a fungus. ... This article or section is in need of attention from an expert on the subject. ... A gamete (from Ancient Greek γαμετης; translated gamete = wife, gametes = husband) is a cell that fuses with another gamete during fertilization (conception) in organisms that reproduce sexually. ... Binomial name Neurospora crassa Shear & B.O. Dodge Neurospora crassa is a type of red bread mold of the phylum Ascomycota. ...


Sperm nuclei

In many land plants, including most gymnosperms and all angiosperms, the male gametophytes (pollen grains) are the primary mode of dispersal, for example via wind or insect pollination, 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 through the carpel. Before the tube reaches the ovule, 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 for fertilization.[1] Divisions Green algae land plants (embryophytes) non-vascular embryophytes Hepatophyta - liverworts Anthocerophyta - hornworts Bryophyta - mosses vascular plants (tracheophytes) seedless vascular plants Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongue ferns seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering... Classes Magnoliopsida - Dicots Liliopsida - Monocots The flowering plants (also angiosperms or Magnoliophyta) are one of the major groups of modern plants, comprising those that produce seeds in specialized reproductive organs called flowers, where the ovulary or carpel is enclosed. ... In plants that undergo alternation of generations, a gametophyte is the structure, or phase of life, that contains only half of the total complement of chromosomes: The sporophyte produces spores, in a process called meiosis. ... SEM image of pollen grains from a variety of common plants: sunflower (Helianthus annuus), morning glory (Ipomoea purpurea), prairie hollyhock (Sidalcea malviflora), oriental lily (Lilium auratum), evening primrose (Oenothera fruticosa), and castor bean (Ricinus communis). ... This article does not cite any references or sources. ... Carpenter bee with pollen collected from Night-blooming cereus Pollination is an important step in the reproduction of seed plants: the transfer of pollen grains (containing the male gametes, sperm) to the plant carpel of flowering plants, the structure that contains the ovule (which in turn houses the female gamete... Amaryllis style and stigmas A carpel is the female reproductive organ of a flower; the basic unit of the gynoecium. ... Pollen may refer to the microspores of either angiosperms (flowering plants) or gymnosperms (conifers and cycads). ... Amaryllis style and stigmas A carpel is the outer, often visible part of the female reproductive organ of a flower; the basic unit of the gynoecium. ... This article or section does not adequately cite its references or sources. ... This article or section does not adequately cite its references or sources. ...


In some protists, fertilization also involves sperm nuclei, rather than cells, migrating toward the egg cell through a fertilization tube. Oomycetes form sperm nuclei in a syncytical antheridium surrounding the egg cells. The sperm nuclei reach the eggs through fertilization tubes, similar to the pollen tube mechanism in plants.[1] Typical phyla Chromalveolata Chromista Heterokontophyta Haptophyta Cryptophyta (cryptomonads) Alveolata Dinoflagellata Apicomplexa Ciliophora (ciliates) Cabozoa Excavata Euglenozoa Percolozoa Metamonada Rhizaria Radiolaria Foraminifera Cercozoa Archaeplastida (in part) Rhodophyta (red algae) Glaucophyta (basal archaeplastids) Amoebozoa Choanozoa Many others; classification varies Protists (IPA: (RP); (GenAm)), Greek protiston -a meaning the (most) first of all... HeLa cells stained for DNA with the Blue Hoechst dye. ... Orders Lagenidiales Leptomitales Peronosporales Pythiales Rhipidiales Saprolegniales Sclerosporales Water moulds or Oomycetes are a group of filamentous protists, physically resembling fungi. ... In biology, a syncytium is a large region of cytoplasm that contains many nuclei. ... Diagram of antheridium anatomy An antheridium (plural: antheridia) is a structure or organ of the gametophyte phase of certain plants producing and containing the spermatids or male gametes. ...


Sperm quality

A study by the University of California has suggested that folate may protect sperm cells from aneuploidy.[1] Berkeley Davis Irvine Los Angeles Merced Riverside San Diego Santa Barbara Santa Cruz UC Office of the President in Oakland The University of California (UC) is a public university system in the state of California. ... Folic acid (the anion form is called folate) is a B-complex vitamin (once called vitamin M) that is important in preventing neural tube defects (NTDs) in the developing human fetus. ... Aneuploidy is a change in the number of chromosomes that can lead to a chromosomal disorder. ...


Market

On the global market, Denmark 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 to remain anonymous to the receiving couple.[5] More than 50 countries worldwide are importers, including Paraguay, the US, Kenya and Hong Kong.[5]


See also

Ejaculation is the ejecting of semen from the penis, and is usually accompanied by orgasm. ... Female sperm is the theoretical concept of a process in which partly developed sperm cells, otherwise known as spermatogonial stem cells, would be created from a females bone marrow stem cells. ... In biology, Polyspermy describes an egg that has been fertilized by more than one sperm. ... Horse semen being collected for breeding purposes. ... Sperm competition is competition between sperm of two or more males for the fertilization of an ovum (Parker 1970). ... Sperm donation is the name of the practice by which a man provides his semen with the intention that it be used to produce a baby where the man does not have sexual relations with the recipient of his semen. ...

References

  1. ^ a b c d e f Raven, Peter H.; Ray F. Evert, Susan E. Eichhorn (2005). Biology of Plants, 7th Edition. New York: W.H. Freeman and Company Publishers. ISBN 0-7167-1007-2. 
  2. ^ Bottino D, Mogilner A, Roberts T, Stewart M, Oster G (2002). "How nematode sperm crawl". J. Cell. Sci. 115 (Pt 2): 367–84. PMID 11839788. 
  3. ^ Sumbali, Geeta (2005). The Fungi. Alpha Science Int'l Ltd.. ISBN 1842651536. 
  4. ^ Maheshwari R (1999). "Microconidia of Neurospora crassa". Fungal Genet. Biol. 26 (1): 1–18. doi:10.1006/fgbi.1998.1103. PMID 10072316. 
  5. ^ a b Assisted Reproduction in the Nordic Countries ncbio.org
Preceded by
None
Stages of human development
Sperm
Succeeded by
Zygote
A digital object identifier (or DOI) is a standard for persistently identifying a piece of intellectual property on a digital network and associating it with related data, the metadata, in a structured extensible way. ... Human development is the process of growing to maturity and reaching ones full potential. ... For other meanings see Zygote (disambiguation). ...

  Results from FactBites:
 
Sperm Whales (Physeter macrocephalus) - Office of Protected Resources - NOAA Fisheries (2080 words)
Sperm whales have the largest brain of any animal (on average 17 pounds (7.8 kg) in mature males), however, compared to their large body size, the brain is not exceptional in size.
Sperm whales tend to inhabit areas with a water depth of 1968 feet (600 m) or more, and are uncommon in waters less than 984 feet (300 m) deep.
Sperm whales have the potential to be harmed by ship strikes and entanglements in fishing gear, although these are not as great of a threat to sperm whales as they are to more coastal cetaceans.
SPERM WHALE (1253 words)
Sperm whales produce ambergris, a dark, waxy substance (related to cholesterol) that is produced in the lower intestines, and is sometimes found containing squid beaks.
Sperm whales also stick their tail out of the water into the air, swing it around, and then slap it on the water's surface; this is called lobtailing.
Sperm whales (Physeter macrocephalus) are toothed whales (Suborder Odontoceti) although DNA analysis shows that the Sperm whale is actually more closely related to the baleen whales.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m