Sperm
hideThe term sperm is derived from the Greek word (σπέρμα) sperma (meaning "seed") and refers to the male reproductive cells. In the types of sexual reproduction known as anisogamy and oogamy, 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 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 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 totipotent zygote is formed with the potential to develop into a new organism.
The spermatozoa of animals are produced through spermatogenesis inside the male gonads (testicles) via meiotic division. They are carried out of the male body in a fluid known as semen. Mammalian sperm cells can live for up to 3 days inside the female reproductive system.[citation needed]
Sperm cells in algal and many plant gametophytes are produced in male gametangia (antheridia) via mitotic division. In flowering plants, sperm nuclei are produced inside pollen.
For more information about Sperm, read the full article at
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News tagged with sperm
For young boys with cancer, testicular tissue banking may be option to preserve fertility
Nov 09, 2009 |
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For parents of children with cancer, the hopeful news is that pediatric survival rates have steadily improved for decades. Among the bad news—treatments that enable survival often cause infertility.
Whales are polite conversationalists
Oct 26, 2009 |
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What do a West African drummer and a sperm whale have in common? According to some reports, they can both spot rhythms in the chatter of an ocean crowded with the calls of marine mammals -- a feat impossible for the untrained ...
Sperm may play leading role in spreading HIV
Medicine & Health / HIV & AIDS
Oct 26, 2009 |
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Sperm, and not just the fluid it bathes in, can transmit HIV to macrophages, T cells, and dendritic cells (DCs), report a team led by Ana Ceballos at the University of Buenos Aires in Argentina. By infecting ...
Sperm donor passed on sudden death heart defect
Oct 20, 2009 |
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(AP) -- A sperm donor passed on a potentially deadly genetic heart condition to nine of his 24 children, including one who died at age 2 from heart failure, according to a medical journal report.
Putting the squeeze on sperm DNA
Sep 30, 2009 |
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(PhysOrg.com) -- In the quest for speed, olympic swimmers shave themselves or squeeze into high-tech super-suits. In the body, sperm are the only cells that swim and, as speed is crucial to fertility, have ...
Childhood kidney disorder has lasting effects
Sep 24, 2009 |
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A kidney condition that can arise in children and was until recently believed to disappear after puberty may persist into adulthood and cause significant long-term complications, according to a study appearing in an upcoming ...
French woman asks court for dead husband's sperm
Sep 23, 2009 |
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A 39-year-old widow asked a French court Wednesday to allow her to retrieve her late husband's frozen sperm so that she can be inseminated and have his child.
Study Positively Identifies Giant Squid Presence in Gulf of Mexico
Sep 21, 2009 |
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(PhysOrg.com) -- During a recent research cruise, a rare giant squid was captured in the Gulf of Mexico.
Taiwan scientists develop sperm 'efficiency' kit
Sep 17, 2009 |
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Scientists in Taiwan said Thursday they have invented a male fertility home test kit that breaks new ground by measuring the efficiency of sperm cells -- a key factor in determining men's ability to father children.
Possible genetic factor for male infertility identified
Sep 15, 2009 |
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Virginia Commonwealth University School of Medicine researchers have discovered a gene involved with the production of sperm that may contribute to male infertility and lead to new approaches to male contraception.
When you've doubled your genes, what's 1 chromosome more or less?
Sep 14, 2009 |
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An individual with Down syndrome and a male calico cat have one thing in common -- each has an extra chromosome. For animals, most instances of an extra chromosome result in birth defects or even death, but plants are another ...
Secrets in a seed: Clues into the evolution of the first flowers
Sep 14, 2009 |
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Approximately 120-130 million years ago, one of the most significant events in the history of the Earth occurred: the first flowering plants, or angiosperms, arose. In the late 1800s, Darwin referred to their development ...
Infertility and the battle of the sexes
Sep 08, 2009 |
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About 10% of all couples hoping for a baby have fertility problems. Environmentalists say pollution is to blame and psychiatrists point to our stressful lifestyles, but evolutionary biologist Dr. Oren Hasson of Tel Aviv University's ...
Mother knows best: Females control sperm storage to pick the best father
Sep 08, 2009 |
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(PhysOrg.com) -- Scientists have found new evidence to explain how female insects can influence the father of their offspring, even after mating with up to ten males. A team from the University of Exeter has ...
Molecular Decay of Enamel-Specific Gene in Toothless Mammals Supports Theory of Evolution
Sep 04, 2009 |
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(PhysOrg.com) -- Biologists at the University of California, Riverside report new evidence for evolutionary change recorded in both the fossil record and the genomes (or genetic blueprints) of living organisms, ...
