Something Sex, Never That Of More!Sunday 29th of January 2012 08:43:39 PM
Dear taringuer@s friends, I want to make this post a small introduction to a topic to which we are all bound by our condition of beings and sexuality allows to nominate all of the anatomical, physiological and psychological conditions that characterize each . The term also refers to the sexual appetite (such as a propensity for carnal pleasure) and the whole of -related behavioral and emotional phenomena.
In antiquity, it was considered that the sexuality of beings and it was instinctive. Sexual behaviors, were therefore determined biologically and all practices that were not addressed to procreation were considered as unnatural.
Sexuality, over time, acquired a social and cultural notion. Currently, is known that specimens of several species have a tendency to homosexuality, practicing different techniques of masturbation or to incur in violations. Beings and , therefore, develop the characteristics of their sexuality according to your environment.
Now friends taringuer@s'll give several examples of sexuality and of and than perhaps most of us desconocíamos and never this from more know them, then see the items:
Why are there only two sexes?
is something universal?
Lol Although about two million currently, only 2,000 described species (0.1 per cent) are sexless estrictame. Most of the non are single-celled organisms, prokaryotes, bacteria, etc., domain that biologists have just begun to learn. So it could be many more. In addition, most sexual species (sponges, corals, some crustaceans and insects) practice times asexual reproduction.
There are species evolved from organisms sexuals, but able to produce offspring with the help of unfertilized eggs. This mechanisms, known as parthenogenesis, also used it some reptiles.
How are males and females differed?
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Gametes (germ cells), had two chances of survival: accumulate many energy resources enable them to expect calm to arrive another sexual cell that merge (strategy to develop eggs), either produce many gametes without just resources, nothing resistant (sperm). Being so many, always one can find another gamete with a different genetic material. The choice of a strategy or another developed two types of individuals: males, bearers of spermatozoa and females, producing eggs. Models has found that it is more likely to appear two unequal gametes that two balanced.
Is the male a parasite of the female?
/ > Some hypotheses raised the parasite evolution of the male into the origins of life (not proven). There are male parasitic forms such as the cerate: the male of this deep-sea fish guarantees his sexual success live stuck to the throat of his "girl".
What is the of hermaphrodites?
They are equipped with male and female, sexual organs so they have two sexes at the same time. This does not always mean that they reproduce themselves. It is the mode of reproduction of numerous : sponges, corals, peces…, but they usually need a companion. In mammals such as humans, it is linked to chromosomal and hormonal abnormalities.
How many sex cells we produce?
200 million sperm by ejaculation and 400 thousand possible eggs for a woman in his life. This imbalance, called anisogamia, is not universal. Mushrooms and single-celled algae, for example, have equality of gametes (isogamy).
Can we get to be non?
In any case, not in a natural way. Homo sapiens has lost the ability to have certain species of reptiles reproduce without males. Our inability to imitate this model has to do with a complex phenomenon called parental genomic fingerprint.The mechanism works in the following way: from the maturation of the egg and sperm in the sexual glands, the specific genes are inactive. Important detail: to a dormant gene for the male is always an active gene of the female, in such a way that the fertilized egg gets to force an active gene. This complementarity means that the egg, to facilitate a viable embryo, need a sperm. This prevents any alternative of self-development.
Why men have penis?
Because mammals have opted for a type of typical internal fertilization of a terrestrial existence. The eggs fertilized in the shelter of the female genital tract, protected from attacks from outside. And a penis helps put sperm in the starting line (overseas, die).
Does cross-dressing exists between ?
Certain fish of the genus Lepomis have male looking for females (more pequeños). When a male is going to the Fund to attract the female and fertilizes her, the transvestites also come, but not to be fertilized, but to take advantage of his disguise and fertilize in turn real females.
X and and had a common origin?
Just decubrirse papayas have one chromosome y. and well? Male chromosome of papayas is the first direct evidence that the sex chromosomes diverged from a single chromosome makes millionyears. Previous research showed that the more were regressing time, more like they were X and and what got married with the idea that both evolved from a pair of identical chromosomes. Now, the papaya gives them the reason.
Why are there gender balance?
The reason for the same number of males to females is not known yet. There are 20% more likely to fertilize a male in the , but 15% of the embryos that do not reach term would have been males, which balances the figure. Among deer, when conditions are favorable birth to 70% of males. The female selects the of sperm that fertilized the egg, but it is not known how. For its part, the female of the Myocastor coypus (a species of Otter) detects when there are too many females in a litter and her aborted.
/ >Curiosities about sex
What substance the women ejaculates?
A liquid clear consistency similar to a light lubricant, that nothing has to do with common moisture that accompanies the excitement on the genitals of women, and it is not urine. A fluid often taboo, and whose existence has been discussed even in seminars of experts. Now there is no doubt: there are women who ejaculates and women than not. The first to speak of it was Ernst Gräfenberg, German scientist who gave his name to the G-spot, the great discovery was in 1981, when the American sexologist Beverly Whiple published the case of a woman who ejaculated in his laboratory. During the climax, he issued a large amount of fluid. Its composition is mainly amixture of prostatic fluid, with minimal traces of urine and glucose. The so-called women's prostate are parauretrales and urethral glands not seen with the naked eye, but they are in the anterior wall of the vagina. Ejaculation has been associated with women whose vaginal wall has more thickness. Among the visitors of porn, referred to as squirting.
When a drug that allows multiple orgasm in men?
Refractory period. With that pompous name scientists described the time after feeling an orgasm when a man thinks about everything but have immediately. This is what prevents the male multiorgasmia. And responsible for this appetite suppression is the segregation of the hormone prolactin. In fact, a German study confirmed the lack of this substance in a patient with a capacity of multiorgásmica. On the other hand, also proved another hormone, dopamine, favours sexual stimulation and, therefore, the erection. These discoveries on both hormones open the way to the possibility of thecreation of a drug multi-orgasmic, which would comprise a dopamine agonist (flattering) and a (limiter) antagonist of prolactin.
What total volume of semen is produced throughout life?
Let us accounts. We know that a man produces 0.4 ml of seminal plasma every day of abstinence, and a volume average of between 2 and 6 ml in each ejaculation, depending on whether it has gone long periods of abstinence or not. If a man begins his "activity" at the age of 10 years and her ends when it meets the 80, could produce some 51 liters of semen, more or less (if chatting he ejaculates 50% of the days to an average of 4 milliliters and the rest of the time remains in abstinence) throughout his life.
It is that the semen is nutritious true?
In its composition are: vitamins and minerals such as calcium, zinc, magnesium, potassium, sodium and even acid Ascorbic (vitamin bienamada C). It also has citric acid, used as a preservative, and inositol, a compound of fashion in some gyms and herbalists for its alleged anabolic capabilities. But these components appear in very small amounts and with such large variations among donors, which only may recommend its consumption for fun, and not for its nutritional effect. On the other hand, the semen also contains fructose, a compound in the human organism into glucose; but in so sparingly that human ejaculation is suitable for diabetics.
How to measure an orgasm?
"border ="0 "src="http://k06.kn3.net/C5B91A52C.png"/ > orgasm is an explosive discharge of sexual tension that translates into a series of rhythmic contractions, in particular from three to 15 every 0.5 seconds of certain muscles. Yes there are averages and records on the duration of the climax (up to 15 seconds), and a scale to measure the phases of orgasm, but none reliable to measure its intensity, because it's a subjective phenomenon. Although there is an iPhone application called Passion that ensures that it is capable of measuring them. Just leave it connected with the site chosen to unleash loose the passion and, once you've finished, it gives you a score taking into account the duration, intensity of orgasm, and activity level. There is nothing!
Why turns it on us to see someone having ?
A study of the school of Medicine of the University of Washington has confirmed that, in a way, our central nervous systemIt is prone to eroticism. In their research, scientists discovered that the brain is activated much faster to "libidinosos" stimuli that other. Dr. Harold Mouras, of the University of Picardie Jules Verne (France), became interested in the way in which our brain reacts to sexual stimuli from pornography, and found that the excitement had been accompanied by an intense activity in the pars opercularis, precisely the region which is lots of neurons mirror, responsible for empathyfor example. So he came to the conclusion that the vision of other persons carrying out a sex act activates our mirror neurons and leads us to think that we are ourselves the protagonists of this action.
When did it pornography?
The oldest sculpture that we know is the Venus of Hohle Fels, found in the German Cave of the same name, and reproduces the body of a woman that airs an overwhelmed vulva and generosísimos breasts. Data of at least 35,000 years ago. When reporting the finding,Paul Mellars, of Cambridge University, claimed in Nature: "According to the standards of the 21st century, this venus touches pornographic". However, if we understand as pornography that recreates the intercourse, would have to go back a few thousand years later, the year 1150 before our era. That's the date of completion of the Turin erotic Papyrus, in the Archaeological Museum of the Italian city, a genuine exercise of pornography that recreates twelve acrobatic positions.
How is the hangover cure?
Despite the fact that it is one of those diseases that almost everyone has suffered at least once, the scientific community has not made adequate studies on the matter. And that there are not conclusive. It is not yet known what the physiological mechanisms that lead to feel thirst, dry mouth, nausea, dizziness... so less how cure it.
Most of these symptoms are related to dehydration. Alcohol is a diuretic and favours the expulsion of fluids. On the other hand, recent studies link some hangover symptoms, such as changes of mood and lossmemory, with the increase in the level of certain cytokines of pro-inflammatory calls and interferon-gamma. The function of both proteins in our body would lead us to conclude that the hangover is an immune response. I.e., our organism defends itself from a substance, alcohol, which has already been completely eliminated.
Why a gin and tonic do us feel good?
Therefore because the moderate consumption of alcohol produces us the release and synthesis of opioid peptides; in other words, the famous endorphins that appear during sexual arousal and drug use, and make us feel good. On the other hand, the tonic is actually quinine with carbonated water. And it is that when quinine was sent to the India as a vaccine against malaria, the English her mixed with carbonated water. So, at the end and all, the gin and tonic is partly medicinal.
Why?We attracted drug?
Dopamine is a hormone produced by your body and which is linked to the feeling of reward and pleasure. The effect of all drugs is related, in one way or another, with the production of this hormone. No wonder, therefore, that these substances have so successful among us: because they make us feel good.
Why they placed us drugs?
This is because it has effects on the perception and consciousness. They are capable of transformingthe operation of different neurotransmitters and brain neurorreceptores. Literally, lead us "of travel", although each do it differently. For example, while the nicotine affects acetylcholine receptors and causes an increase in brain activity, heroin affects opioid receptors, which causes both the absence of pain and the feeling of euphoria. In the case of LSD, its effects on serotonin receptors induce a transformation of consciousness levels.
Why are we on drugs?
When we usually take a drug, our brain reduces the natural production of dopamine. That is why, if we abandon the substance, we feel bad: our body yearns for the former contribution of that "the pleasure hormone". But it happens that, somehow, to produce one have made us dependent on external stimuli.
However, not all people that test a drug are snagged equal. Researchers at the University of Cambridge have shown, in a study with rats, that some of themthey experienced a more compulsive behavior than their peers, due to an inhibition in an area of your brain called the nucleus accumbens dopamine production naturally. They were, therefore, more likely to seek the dopamine in external substances. The translation of this study could explain why some are more prone to addictions than others.
Is there a drug placebo?
In many drugs, his main problem is not so much that they are harmful as the fact that hooked. A substance taken in small amounts, may not adversely affect the Agency, but administered in excess goes so far as to be life-threatening. And when one becomes addicted, just feeling that any amount is low. The most extreme example it would have in the wine. It is an alcoholic beverage, and as such, you can create addiction. However, consumed in small quantities has an effect that we might even consider as medicinal. It has been shown that those people who make a moderate consumption of wine (between one and three drinks a day) have manyless likely to suffer a cardiovascular crises. This should add the discovery of other prominent components of this liquid, polyphenols, whose antioxidant power prepares us against diseases such as the Alzheimer and the párkinson. However, when there is a step beyond the moderate consumption, wine shows another face: is addictive and harmful to the liver, also that it favours the development of cancers such as stomach and esophagus. Throughout history, drugs such as cocaine, amphetamines and even heroin began being praised for its positive effects, to end up being classified as highly dangerous substances.
Why are breasts attract men?
Like the wide hips, her abundant breasts are indicative of high levels of estrogen in women and, by extension, of fertility. Another hypothesis adventure big breasts selected evolutionarily as a sign of sexual when our species began to walk upright and the coitus began to practice face-to-face. The neuroscientist Larry Youngan interesting theory published in Nature in 2009. It is that, according to Young, human love is turned on by a "chain of biochemical events" that decide the mother-infant relationship, and that is stimulated in mammals through the release of oxytocin during childbirth, childbirth and breastfeeding. "Something of our sexuality has evolved to encourage that same system of oxytocin to set links between women and men," said the doctor Young.
This hypothesis would explain, according to him, two differences between and non-monogamous mammals: the desire for the females having outside their fertile phase, as well as the erotic fascination of the male breasts. with more frequency and greater attention to her breasts, as he claimed the doctor Young at New York Times: "can help to build links in the long term through a"cocktail of ancient neuropeptides", such as oxytocin released during prior to sexual intercourse or orgasm sex games".
We all have sexual fantasies?
18pt; line-height: 18pt ">fantasies has who wants them to have." As is the case with masturbation, fantasies have always been, at least culturally, purely male heritage. In a society burdened by the idea that only men have sexual desire, fantasies, which is almost always above based on go a little beyond the conventional, were taboo for females. Surveys seem to confirm that, although the sexual fantasies have no gender, men yes drift more than women.
Thus, a survey in Spain established by 71% the percentage of men who acknowledged having sexual fantasies, while the figure was reduced to 48 per cent in women. Some theorists believe that this gender gap has an evolutionary basis, since human females would require looking for stability with their partners, unlike the males, who would be ready for any meeting, by shooting it.
There are women who reach orgasm with the stimulation of the nipples?
YesThere is orgasm through stimulation of the nipples, and there are numerous women who bear witness. Science, also confirmed that stimulation of the breasts generates a significant rise in the levels of oxytocin, a hormone linked to the pleasurable sensation. However, are not in agreement on whether the stimulation of the breasts directly produces the climax in the genital area or said orgasm would have a character itself, not genital, exclusively produced in the brain. And there is no unanimity in the number of women who can thus the climax, since there are studies that circumscribe it to 1% of the females, while others rise that privilege to 29%.
Tell me how do you it...
It is able to acclimate to any type of sexual organization. More or less stable couples life is the most widespread type of coexistence between the especid, which does not exclude others.
These apes are peaceful and egalitarian groups practice multiple copulation, between many males and females.
Males join together to stop form coalitions, and the females are divided among the various groups.
The dominant male of the group controls several females at the same time. The copula is polygamous.
They are characterized by exemplary lonely and violent. The copula is scattered and wild.
The Gibbons are monogamous (an unusual feature among primates) and live in family groups that consist of an adult pair and their young offspring. Family will monitor its territory and defend it through strong howls, which can resound km.
style = "font-family: Verdana" > sex on the farm
These are really monkeys
Because the marmosets share the placenta in the womb, his blood is mixed and they have cells of his brother. Therefore, when a new litter, is born no one is sure of what cells have continued the lineage. Thus, parents and uncles become amantísimos parents, no matter who are young.
Father if there is more than one
Parenthood changes to more than one and surprise to almost everyone. At least, when speaking of the Weaver fish (pictured), made with the best females if before it has proven that you can care for their offspring properly. It is also the case of the barking Toad: stays with the eggs until hatch, wetting them with their urine so that they do not lose moisture.
Por una cabeza
According to William Brown, of the University of New York: "the male of the mantis assesses the risk of a sexual encounter and alter their behavior to reduce it." "This depends on factors such as opportunities more secure of mating, the age of the male and the female quality".
Aphids (aphids), like , have bacteria inside your body, many of which are useful. One of them, the Hamiltonella defensa, is particularly valuable because it killed parasitic WaSP larvae before they begin to grow inside the body. A áfida female can get these bacteria practicing with infected males, and thus to pass them
to their future clones.
It serves only to that
The male of the Fire Ant is, according to Dennis Fournier, of the free University of Brussels: "A sperm with legs". While the Queen produces clones of herself, only males fertilized eggs to be sterile workers. Additional males are born when the eggs that puts the Queen contain nothing of their genetic material.
The rotifers, microscopic that carry 80 million years without , have a trick to deal with developments: horizontal gene transfer; i.e. pass genetic material to a cell not descendant and also to receive her. Discovered by analyzing the rotífero Bdelloid genome: it was found that it was crowded of genes from bacteria, fungi and plants.
Drink with straw
The female of the weevil from the Jewish (Acanthoscelides obtectus) has a strange, when less usual, in
which refers to reproduction: prefers to drink the semen of the male before that use it to fertilize the eggs. These go straight to the sheath of the plant where they develop. Also it is quite extraordinary, compared with the human, the duration of sexual intercourse: arrive after 16 minutes. The females live approximately 5 weeks.
My husband? In my womb!
"border ="0 "src="http://k06.kn3.net/C5B91A52C.png"/ > the bonelia female hosts a harem of males (up to 20) in her own womb. "Husbands", which have arrived there matted by the body of the female and introducing into his mouth, live as parasites, so get eaten by the female. But this is a relationship of mutual benefit: the female can fertilize the eggs without having to invest efforts in seeking couple.
Sex without males
Researchers of the Field Museum of Chicago have confirmed through genetic analysis, that a female shark Dogfish psammodromus gave birth two pups without having had any male contact. This suggests that parthenogenesis may not be an impasse of evolution.
24pt; line-height: 24pt ">strategies to flirt "
The Virgin Dragon
Flora is a Zoo, Chester, England Komodo dragon. Eager to have offspring and no males of his species nearly, put eggs on their own in 2006. It left scientists when they found that the genetic material of their cescendientes was only theirs. He had reproduced through parthenogenesi