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Organisms of many species are specialized into male and female varieties, each known as a sex. Sexual reproduction involves the combining and mixing of. Get the latest sex news, articles, videos and photos on the New York Post. Sex, dating and relationship news from The Independent. Browse The Independent's complete collection of articles and commentary on Sex here.

Organisms of many species are specialized into male and female varieties, each known as a sex. Sexual reproduction involves the combining and mixing of. Statistically Speaking, Someone Is Going to Have Sex in the Cybertruck VICE meets two married women who work as sex workers at the same brothel. Get the latest sex news, articles, videos and photos on the New York Post.

What does sex mean? sex is defined by the lexicographers at Oxford Dictionaries as (chiefly with reference to people) sexual activity, including specifically. Statistically Speaking, Someone Is Going to Have Sex in the Cybertruck VICE meets two married women who work as sex workers at the same brothel. Both were members of online chat groups that shared secret sex tapes and made jokes about drugging and raping women, the Seoul Central.

Sharing personal information brings people closer together. Verified by Psychology Today. From attraction to action, sexual behavior takes many sex.

At least for humans, this most basic of activities is anything but basic. As the pioneering sex researcher Alfred Kinsey put sexx, the only universal in human sexuality is variability itself. Human interest in sex is not a matter left to chance but more a built-in imperative; survival of the species depends on it. Although sexual desire may wax and wane over the life cycle, depending on life demands and relationship satisfaction, the decks are stacked in sex's favor, as a passport to bondingto intimacyto pleasure, and even to human growth and sxe.

People normally engage in sexual activity for any number of reasons—to feel alive, to maintain a vital aspect of human functioning, to feel desirable and attractive, to achieve closeness, to please a partner they love.

Bodies and interests change over the course of time, and the complexities of physiology and psychology mean that most people experience a sexual problem at some point in their lives. Although sex can be one of the most difficult topics for partners to discuss, it's one that also stands to draw couples closer together. The moral and political implications of sex vary greatly from culture to culture, and even within cultures and over time; still, there is agreement on one certainty: It's why we're alive today and what future generations depend on.

Desire is part biology, sex psychology, often as subtle as it is predictable, and takes shape differently in men and women. For men, arousal typically precedes desire. But for women, desire precedes arousal, in response to physical intimacy, emotional connection, and sex atmosphere free of distractions and everyday concerns.

Scientists are continuously exploring the interplay of biological influences, such as neurohormones that suppress or enhance desire, and psychological influences, such as emotions and relationships. Smell plays an often subtle role in attraction; research shows that women are attracted sex mates whose natural body odor sometimes referred to as pheromones signals a genetic profile distinct from their own. Low sexual desire is a common occurrence, among both sexes, and often it can be resolved by regularly exchanging affection and conversation outside the bedroom as well as in it, making sufficient time sex each other and for sex, and addressing conflicts within a relationship.

Given the enormous variability in activities that people find arousing, there is no one way to be sexual. Men are especially stimulated by visual imagery, and about 90 percent of young men report using pornography with some regularity, sometimes because they lack a partner or don't know how to bridge the differences in sexual appetite and interest that can occur between partners in the absence of discussion of their sexual pleasures, and sometimes for convenience.

Many people engage in behaviors that were once perceived as atypical, such as dominance play and sex intercourse. Researchers know that flexibility in sexual repertoires is healthy and generally enhances relationships; they regard a specific behavior as problematic only when it creates harm or distress for one or both partners or when the behavior is compulsive—that is, it becomes the only means of arousal.

Sexual behavior changes over time as a reflection of age, experience, and one's relationship. And the trajectory of change may vary between men and women. Women may encounter difficulties in navigating cultural attitudes about sexual behavior and promiscuity as eex first explore their sexuality; age brings confidence and skill at communication that can enhance sex life. Young men often have concerns about performance, penis size, or premature ejaculation—and anxiety is no friend sex performance for either men or women.

Men often experience challenges sex arousal and erectile dysfunction as they age. Couples tend to report that their esx life is most robust when they are in their 30s and 40s, but sex life is often most deeply rewarding for older partners. People can enjoy satisfying sex seex the lifespan if they make adjustments for the many changes that time brings; that can mean relying less on penile penetration and more on massage, whole-body touching, and oral sex.

Since sexuality varies so widely, most behaviors, preferences, and quirks are encompassed in healthy sexual activity. Dex behavior only shifts into a disorder when it leads to significant distress, threatens to harm others, or becomes compulsive.

Sexual disorders are a diverse collection of experiences and conditions. Erectile disorder, also called erectile dysfunction, is a chronic inability to get or maintain an erection.

Sexual Desire Disorder is lacking any drive for sex over a prolonged period. Orgasmic Disorder may be diagnosed when a woman is not able to reach orgasm, and Genito-Pelvic Pain or Penetration Disorder refers to experiencing extreme pain during penetrative sex. For more information on sex, causes, and treatments for each disorder, visit our Diagnosis Dictionary.

Compulsive BehaviorsEsx. By Mark Travers Ph. By Marianne Brandon Ph. In fact, cultivating this tender emotion can deepen and expand a romantic relationship. By Mellissa Withers, Ph. S on November 22, sex Modern Day Slavery. While social media has been a force for good in drawing attention to sexual harassment, it has also offered sex traffickers a new avenue through which to ensnare victims.

By Karla Ivankovich Ph. The risks of telling your partner they suck in the sack. What do you have to lose other than great sex? Science has shown that boosting Oxytocin can improve your social intelligence and make you feel more connected. By Elizabeth Letourneau, Ph. The time has come to enact effective perpetration prevention efforts. By Carol A. By Justin J Lehmiller Ph. We have a tendency to believe that progress makes everything better, including sex; however, Chris Ryan's new book suggests that this line of thinking may be all sez.

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Back Psychology Today. Back Find a Therapist. Back Get Help. Sfx Magazine. The Power of Boundaries Sharing personal information brings people closer together.

Subscribe Issue Sez. Back Today. In Praise of the Idle Mind. The Evidence on Giving Thanks. How Does Desire Emerge? What Leads to Arousal? What Are the Different Sexual Disorders? Essential Reads. S on November 22, in Modern Day Slavery While social media has been a force for good in drawing attention to sexual harassment, it has also offered sex traffickers a new avenue through which to ensnare victims.

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Many plants, including conifers and grasses, produce lightweight pollen which is carried by wind to neighboring plants. Other plants have heavier, sticky pollen that is specialized for transportation by insects. The plants attract these insects or larger animals such as humming birds and bats with nectar-containing flowers.

These animals transport the pollen as they move to other flowers, which also contain female reproductive organs, resulting in pollination. Most fungi reproduce sexually, having both a haploid and diploid stage in their life cycles.

These fungi are typically isogamous , lacking male and female specialization: haploid fungi grow into contact with each other and then fuse their cells.

In some of these cases, the fusion is asymmetric, and the cell which donates only a nucleus and not accompanying cellular material could arguably be considered "male". Some fungi, including baker's yeast , have mating types that create a duality similar to male and female roles. Yeast with the same mating type will not fuse with each other to form diploid cells, only with yeast carrying the other mating type.

Many species of higher fungi produce mushrooms as part of their sexual reproduction. Within the mushroom diploid cells are formed, later dividing into haploid spores. The height of the mushroom aids the dispersal of these sexually produced offspring. The most basic sexual system is one in which all organisms are hermaphrodites , producing both male and female gametes— [ citation needed ] this is true of some animals e.

The biological cause for an organism developing into one sex or the other is called sex determination. The cause may be genetic or non-genetic.

Within animals and other organisms that have genetic sex systems, the determining factor may be the presence of a sex chromosome , or it may be other genetic differences. Non-genetic systems use environmental cues, such as the temperature during early development, to determine the sex of the offspring. In the majority of species with sex specialization, organisms are either male producing only male gametes or female producing only female gametes.

Exceptions are common—for example, the roundworm C. Sometimes an organism's development is intermediate between male and female, a condition called intersex. Sometimes intersex individuals are called "hermaphrodite"; but, unlike biological hermaphrodites, intersex individuals are unusual cases and are not typically fertile in both male and female aspects.

In genetic sex-determination systems, an organism's sex is determined by the genome it inherits. Genetic sex-determination usually depends on asymmetrically inherited sex chromosomes which carry genetic features that influence development ; sex may be determined either by the presence of a sex chromosome or by how many the organism has. Genetic sex-determination, because it is determined by chromosome assortment, usually results in a ratio of male and female offspring.

Humans and other mammals have an XY sex-determination system : the Y chromosome carries factors responsible for triggering male development. The "default sex," in the absence of a Y chromosome, is female-like. Thus, XX mammals are female and XY are male.

In humans, biological sex is determined by five factors present at birth: the presence or absence of a Y chromosome which alone determines the individual's genetic sex , the type of gonads , the sex hormones , the internal reproductive anatomy such as the uterus in females , and the external genitalia.

XY sex determination is found in other organisms, including the common fruit fly and some plants. In birds, which have a ZW sex-determination system , the opposite is true: the W chromosome carries factors responsible for female development, and default development is male.

The majority of butterflies and moths also have a ZW sex-determination system. In both XY and ZW sex determination systems, the sex chromosome carrying the critical factors is often significantly smaller, carrying little more than the genes necessary for triggering the development of a given sex.

Many insects use a sex determination system based on the number of sex chromosomes. This is called X0 sex-determination —the 0 indicates the absence of the sex chromosome. All other chromosomes in these organisms are diploid, but organisms may inherit one or two X chromosomes. In field crickets , for example, insects with a single X chromosome develop as male, while those with two develop as female.

Other insects, including honey bees and ants , use a haplodiploid sex-determination system. This sex-determination system results in highly biased sex ratios , as the sex of offspring is determined by fertilization rather than the assortment of chromosomes during meiosis.

For many species, sex is not determined by inherited traits, but instead by environmental factors experienced during development or later in life. Many reptiles have temperature-dependent sex determination : the temperature embryos experience during their development determines the sex of the organism. Many fish change sex over the course of their lifespan, a phenomenon called sequential hermaphroditism.

In clownfish , smaller fish are male, and the dominant and largest fish in a group becomes female. In many wrasses the opposite is true—most fish are initially female and become male when they reach a certain size. Sequential hermaphrodites may produce both types of gametes over the course of their lifetime, but at any given point they are either female or male.

In some ferns the default sex is hermaphrodite, but ferns which grow in soil that has previously supported hermaphrodites are influenced by residual hormones to instead develop as male. Many animals and some plants have differences between the male and female sexes in size and appearance, a phenomenon called sexual dimorphism. Sex differences in humans include, generally, a larger size and more body hair in men; women have breasts, wider hips, and a higher body fat percentage.

In other species, the differences may be more extreme, such as differences in coloration or bodyweight. Sexual dimorphisms in animals are often associated with sexual selection —the competition between individuals of one sex to mate with the opposite sex. In many cases the male of a species is larger than the female. Mammal species with extreme sexual size dimorphism tend to have highly polygynous mating systems—presumably due to selection for success in competition with other males—such as the elephant seals.

Other examples demonstrate that it is the preference of females that drive sexual dimorphism, such as in the case of the stalk-eyed fly. Other animals, including most insects and many fish, have larger females. This may be associated with the cost of producing egg cells, which requires more nutrition than producing sperm—larger females are able to produce more eggs. Some plant species also exhibit dimorphism in which the females are significantly larger than the males, such as in the moss Dicranum [46] and the liverwort Sphaerocarpos.

In birds, males often have a more colourful appearance and may have features like the long tail of male peacocks that would seem to put the organism at a disadvantage e.

One proposed explanation for this is the handicap principle. From Wikipedia, the free encyclopedia. This article is about sex in sexually reproducing organisms. For the act, see Sexual intercourse. For other uses, see Sex disambiguation. Main article: Evolution of sexual reproduction. Different forms of anisogamy : A anisogamy of motile cells, B oogamy egg cell and sperm cell , C anisogamy of non-motile cells egg cell and spermatia.

Different forms of isogamy: A isogamy of motile cells , B isogamy of non-motile cells, C conjugation. Main article: Sexual reproduction. Further information: Isogamy and Anisogamy. Main article: Sexual reproduction in animals. Main article: Plant reproduction. Female left and male right cones are the sex organs of pines and other conifers.

Main article: Mating in fungi. Main article: Sex-determination system. Main article: Environmental sex determination. Main article: Sexual dimorphism.

OUP Oxford. Retrieved 23 March Sex: Either of the two main categories male and female into which humans and most other living things are divided on the basis of their reproductive functions. The fact of belonging to one of these categories. The group of all members of either sex. Purves, David E. Sadava, Gordon H.

Orians, H. Craig Heller Life: The Science of Biology. A single body can function as both male and female. Sexual reproduction requires both male and female haploid gametes. In most species, these gametes are produced by individuals that are either male or female. Species that have male and female members are called dioecious from the Greek for 'two houses'. In some species, a single individual may possess both female and male reproductive systems.

Such species are called monoecious "one house" or hermaphroditic. The Fungi. Elsevier Science. Retrieved 18 February Biology of Plants 7th ed. NY: Freeman and Company Publishers. Genetics: Conjugation 4th ed. University of Texas. Biological Science 3rd ed.

Pearson Prentice Hall. Living at Micro Scale. Cambridge, Massachusetts: Harvard University Press. The Evolution of Sex Determination. Oxford University Press. Jupiter Scientific. Retrieved 7 April Proceedings: Biological Sciences. Sex determination in multicellular organisms and protistan mating types".

Seminars in Cell and Developmental Biology. Evolutionary Origin and Adaptive Function of Meiosis. Chapter 3: pp. Life Sci. Bibcode : Natur. Genome Res. National Institutes of Health, " V. The Benefits of Sex ". Meiosis", U. NIH, V. Multicellularity: Evolution of Differentiation". Mul , NIH. Retrieved 4 June Caenorhabditis Elegans: Development as Indiv. Cell", U. Mendelian genetics in eukaryotic life cycles", U. NIH, 3. Sperm", U. Eggs", U. Fertilization", U. Eastern Kentucky University.

Retrieved 3 April Gamete Production in Angiosperms", U. NIH, 4. Kaiser; Arnold Berk; Monty Krieger We have all the latest news, features and stories on the most Googled subject on the internet — with everything from personal first-person pieces to recently launched sex toys.

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