Sperm in Biological News

Spread your sperm the smart way

... Attractive males release fewer sperm per mating to maximise their chances of producing ... mate with many different males. Each male's sperm competes with that of other males in a process ... means it is optimal for him to contribute fewer sperm per mating. Although this reduces fertility per ...

Size did matter

... The mystery of giant sperm present in some living animal groups today has ... fossilised evidence for reproduction using giant sperm in a group of small aquatic crustaceans, called ... Since modern ostracods still produce giant sperm and manoeuvre them with the same organs as 100 ...

Mothers give interloper's offspring a head start in life

... infertile. "Because females can often store sperm for several weeks, they may typically only ... laid eggs." Even if females obtain a mix of sperm before laying, it is possible that the sperm from extra-pair males is more successful in ...

American Chemical Society Weekly PressPac -- April 8, 2009

... RELEASE Solving the mystery of what puts sperm "in the mood" Journal of Proteome Research ... of key biochemical changes that put sperm "in the mood" for fertilization. Their study, ... Platt and colleagues note in the new study that sperm cannot fertilize an egg immediately after ...

Small RNAs can play critical roles in male infertility/contraception

... indicate that the X chromosome in developing sperm cells encodes numerous tiny ribonucleic acids ... roles in chromosome inactivation and also in sperm formation. "The sex chromosome ... role of these small RNA species in the control of sperm production. Worldwide, one in nine couples in ...

Gene discovery could lead to male contraceptive

... models that lack the CATSPER1 gene reveal how sperm is affected when the protein is missing or ... These studies show that CATSPER1 mutations affect sperm motility, specifically the very vigorous hyperactive motion the sperm uses when it is entering the egg during ...

Plant biologists discover gene that switches on 'essence of male'

... reproductive cells to divide to form twin sperm cells. Their study is reported in the journal ... plants, unlike animals require not one, but two sperm cells for successful fertilisation. One sperm cell to join with the egg cell to produce the ...

CSHL scientists discover how 'companion' cells to sperm protect them from genetic damage

... Cold Spring Harbor, N.Y. In plant pollen grains, sperm cells, which carry the genetic material to be ... vegetative cells. These companions provide sperm with energy and nourishment, and push them ... has discovered that the companion cells provide sperm with more than just succor. They also provide ...

The more promiscuous the female, the speedier the sperm

... appears to have triggered changes in the type of sperm a male produces, according to new research on ... how competition for reproduction influences the sperm of many species of African cichlids. These fish ... we found that males produced larger and faster sperm than in closely related species that were ...

February 2009 highlights from Biology of Reproduction

... in the reproductive system, and their sperm have decreased ability to fertilize due to poor ... to previously unsuspected pathways regulating sperm function. But perhaps more importantly, they are of great clinical significance: because sperm of chronic marijuana users, as well ...

Attitudes towards assisted reproduction and preimplantation genetic diagnosis

... Sweden, the Netherlands and France. USING sperm BANKS GETS APPROVAL IN THE CASE OF COUPLES WHERE ... IS INFERTILE Finally, acceptance of the use of sperm banks to conceive a child by assisted ... In all countries, a majority see using a sperm bank as acceptable in the case of couples wanting ...

Boy or girl? It's in the father's genes

... the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. An X chromosome ... as-yet undiscovered gene controls whether a man's sperm contains more X or more Y chromosomes, which ... On a larger scale, the number of men with more X sperm compared to the number of men with more ...

Keeping chromosomes from cuddling up

... II plays a key role in making sure that fruit fly sperm cells each receive the proper number of ... II plays the same role in the formation of human sperm and eggs. Having too many or too few chromosomes in egg or sperm cells is the source of several important genetic ...

First at-home test for vasectomized men proves to be safe, accurate

... rate of 96 percent in identifying whether sperm counts were greater or less than a threshold of 250,000 sperm per ml a level associated with little or no risk ... to be 100 percent accurate in identifying whether sperm counts were greater or less than ...

Biologists discover gene behind 'plant sex mystery'

... plants, unlike animals require not one, but two sperm cells for successful fertilisation. The ... how each single pollen grain could produce 'twin' sperm cells. One to join with the egg cell to produce ... reproductive cells to divide to form twin sperm cells. Professor Twell said: "This ...

Proteins in sperm unlock understanding of male infertility says new study

... Proteins found in sperm are central to understanding male infertility and ... infertility, helping identify which proteins in sperm cells are dysfunctional. "Up to 50 percent of ... 'this is the protein that is misregulated in your sperm and this is the drug that corrects it or ...

Low sperm count may be associated with prenatal testosterone excess

... may be a potential risk factor for low sperm count and motility, according to a new study ... Society. "The majority of disorders affecting sperm count in humans are originated during fetal ... in body weight, scrotal circumference, and sperm count in male sheep born to these mothers ...

Unique study shows oil, gas seismic work not affecting Gulf sperm whales

... gas seems to have minimal effect on endangered sperm whales in the Gulf of Mexico, say researchers ... of its type ever undertaken and formally titled sperm Whale Seismic Study in the Gulf of Mexico, was ... thousands of yards distant does not drive away sperm whales living in the Gulf," Biggs explains. ...

W.M. Keck Foundation grant funds reproductive science research

... and early embryonic development. The egg and sperm unite at the time of fertilization and create a ... forming a new individual. How do the egg and sperm mature, and what is the underlying mechanism that ... is focused on an unexplored area of egg and sperm biology, namely, the relationship of ...

Diabetes linked to male infertility; excess sugars in the body have direct effect on sperm quality

... a significant decrease in their ability to repair sperm DNA, and once this is damaged it cannot be ... a direct influence on the health of semen." sperm DNA quality is known to be associated with ... cancers. Over the years possible causes for sperm DNA fragmentation have been suggested but to date ...

Normal-looking sperm may have serious damage; scientists urge more care in selection

... . Barcelona, Spain: Intracytoplasmic sperm injection (ICSI), where a single sperm is injected into an egg to fertilise it, is ... help infertile men father children. Although the sperm chosen for the procedure may appear quite normal, ...

July 2008 highlights

... role of metabolic enzymes and ATP production in sperm function, it is now shown that one lactate ... fertile. The fertility defects include impaired sperm motility, reduction of capacitation-related ... for glycolysis and ATP production in the sperm tail, and this finding may lead to new insights ...

Biologists find unusual plant gene: abstinence by mutual consent

... the precise delivery of the male reproductive sperm cell to the female egg cell. Fertilization requires fusion of the sperm and egg cells. In flowering plants, the male pollen tube carries sperm cells through the maternal tissues to deliver ...

USC researchers explore genetic causes for male infertility

... of DNA from each mans sperm. They found that sperm DNA from men with low sperm counts or abnormal sperm had high levels of methylation, which is one of ...

Mutant sperm guide clinicians to new diseases

... that some of these rearrangements were found in sperm much more frequently than expected. In work ... on four clinically important regions using human sperm cells as our population of genomes. "Sperm ... rare: we see them in about 1 in 50,000 sperm cells," explained Dr Hurles. "These are ...

New evidence for female control in reproduction

... of female mammals can sense the presence of sperm and react to it by changing the uterine ... several partners play a role in determining which sperm fertilizes their egg. Lead author Alireza ... team reports the first chemical evidence of a sperm recognition system in the oviducts of pigs ...

Contraception: progress brings hope for new methods for men

... similarity to humans.) The monkeys had no moving sperm after they took a compound called CDB-4022, and ... Undecanoate (DMAU), was effective at reducing sperm numbers in rabbits if taken at a low, but not ... a study of 90 men. The Intra Vas Device blocks sperm in the vas deferens, the ...

Primate sperm competition: speed matters

... of primate species has occurred at the level of sperm cell motility. In a paper published online by the ... Ph.D. candidate Jaclyn Nascimento reported that sperm cells from the more promiscuous chimpanzee and ... so that a male with faster and stronger swimming sperm cells would in theory be more likely to ...

Salmon garnish points the way to green electronics

... His answer? Salmon sperm. Salmon sperm is considered a waste product of the fishing ... says Steckl, again smiling. Im receiving salmon sperm from researchers around the world wanting to see if their sperm is good enough. The next step is to now replace ...

Sex is thirst-quenching for female beetles

... water with the sperm, a male can help ensure his sperm has more time to fertilize the eggs without having to compete with the sperm from future matings. Dr Martin Edvardsson of the ... Also, while many female insects can store live sperm inside for long periods of time, females of these ...

Restoring sight, advances in fertility treatments and better visibility for pilots at FIO

... Better, Stronger, Faster: High-Throughput sperm Sorting Detecting Malaria with Light Gigantic ... Better, Stronger, Faster: High-Throughput sperm Sorting Researchers at the University of ... have developed a rapid new sorting technique for sperm using a laser trap that can separate stronger, ...

Not 1, but 2 kinds of males found in the invasive round goby

... and space." The McMaster scientists compared the physical, hormonal and sperm traits of hundreds of males, and found that the nest-guarding, parental ... heads. Both types of males produced sperm, but sneakers produced more sperm than the parental males, and had bigger testes. By contrast, parental ...

Genital stimulation opens door for cryptic female choice in tsetse flies

... of changes in female reproduction, including reduced ovulation, reduced sperm storage and increased re-mating attempts by the females. "To the best of ... Rica. Cryptic female choicethe ability of females to control which sperm reaches their eggs during and after the mating processleads to rapid ...

The egg makes sure that sperm don't get too old

... University of Gothenburg, Sweden, has now shown that a fertilising sperm can get help from the egg to rejuvenate. The result is an important step ... The discovery that the egg cell can extend the telomeres of a fertilising sperm cell is important in the development of stem cell therapy. Stem cell ...

A BBVA Foundation project comes up with a system enabling detection of cetacean hearing loss

... and thus evaluate its survival chances on release. ELUCIDATING THE sperm WHALE SONAR AND ITS DETECTION POWERS Cetacean hearing systems are ... Andr has developed analysis models for the sound signal sequences that sperm whales emit while foraging in the ocean deeps, which conclude that this ...

ACS PressPac -- Sept. 17, 2008

... in China have identified key proteins in men that suppress production of sperm and could become new targets for a future male birth control pill. Their ... production of sperm. Building on a previous study showing almost total sperm suppression with an injectable testosterone combined with a synthetic ...

Research expedition on corals and global warming: Aug. 17-26 in Puerto Rico

... wild. "It looks like it's snowing," she said, "except that the egg and sperm packets rise underwater to the surface rather than fall to the ground." ... small rearing chambers, she will place eggs from certain populations with sperm from certain other populations. Over the next seven days, she will raise ...

UT Knoxville professor finds unexpected key to flowering plants' diversity

... plants -- known as angiosperms -- to quickly and efficiently move sperm from pollen to egg through a part of the plant was the key to their ... to fertilize, pollen that lands on the flower must grow a tube to carry sperm to the egg. In non-flowering plants, the pathway is usually short, because ...

Obese men have less semen, more sperm abnormalities, and should lose weight before trying for a baby

... an optimal BMI (20-25, as classified by WHO), had higher levels of normal sperm than those in the other groups. They also had higher semen volume. There was no significant difference between the four BMI groups in sperm concentration or motility. The researchers did not look at DNA damage ...

Variety is the spice of life: too many males, too little time...

... population. Female painted dragons possess the remarkable ability to store sperm inside their reproductive tract that remain viable for a considerable amount of time, so that the sperm of different males actually compete with each other to fertilise her eggs. ...