Article : SEX

Sex
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This article is about biological sexes: male, female, etc.. For alternate uses, such as sexual intercourse, see Sex (disambiguation).

Sexuality Portal
Sex refers to the male and female duality of biology and reproduction. Unlike organisms that only have the ability to reproduce asexually, many species have the ability to produce offspring through meiosis and fertilization. Often, individuals of the two sexes attract one another and communicate their readiness to procreate through biological changes, or, in social species, through courtship behaviours.
An organism's sex is defined by its biological role in reproduction, not according to its sexual or other behavior. The female sex is defined as the one which produces the larger gamete and which typically bears the offspring. In contrast, the male sex has a smaller gamete and rarely bears offspring. In some animals and many plants sex may be assigned to specific structures rather than the entire organism. Earthworms, for example, are normally hermaphrodites.

Contents[hide]
1 Sexual reproduction
2 Animal species
3 Humans
3.1 Social and psychological issues
4 See also
5 References
6 Sources
7 External links and further reading
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Sexual reproduction

Hoverflies mating
Sexual reproduction is a prevalent system for producing new individuals within various species. Individuals of sexually reproducing species produce special kinds of cells called gametes, whose function is specifically to fuse with one unlike gamete and hence form a new individual. This fusion of two gametes is called fertilization. The condition of having types of gametes that are externally similar—particularly in size—is isogamy; having gametes that are somewhat dissimilar is anisogamy. The condition of having greatly dissimilar gametes—particularly a large, immotile cell and a much smaller, motile one—is oogamy. By convention, the larger gamete cell is associated with female sex. Thus an individual that produces exclusively large gametes (ova in humans) is said to be female, and one that produces exclusively small gametes (spermatozoa in humans) is said to be male. An individual that produces both types of gametes is called hermaphrodite (a name applicable also to people with one testis and one ovary). In some species hermaphrodites can self-fertilize, in others they can achieve fertilization with females, males or both. Some species, like the Japanese Ash, Fraxinus lanuginosa, only have males and hermaphrodites, a rare reproductive system called androdioecy‎.
What is considered defining of sexual reproduction is the difference between the gametes and the binary nature of fertilization. Multiplicity of gamete types within a species would still be considered a form of sexual reproduction. However, of more than 1.5 million living species,[1] recorded up to about the year 2000, "no third sex cell — and so no third sex — has appeared in multicellular animals."[2][3][4] Why sexual reproduction has an exclusively binary gamete system is not yet known. A few rare species that push the boundaries of the definitions are the subject of active research for light they may shed on the mechanisms of the evolution of sex. For example, the most toxic insect,[5] the harvester ant Pogonomyrmex, has two kinds of female and two kinds of male. One hypothesis is that the species is a hybrid, evolved from two closely related preceding species.
Fossil records indicate that sexual reproduction has been occurring for at least one billion years.[6] However, the reason for the initial evolution of sex, and the reason it has survived to the present are still matters of debate, there are many plausible theories. It appears that the ability to reproduce sexually has evolved independently in various species on many occasions. There are cases where it has also been lost. The flatworm, Dugesia tigrina, and a few other species can reproduce either sexually or asexually depending on various conditions.[7]

Animal species
Main articles: Animal sexuality and Mating system
Animal sexual behavior takes many different forms, even within the same species. Researchers have observed monogamy, promiscuity, sex between species, sexual arousal from objects or places, rape, necrophilia, sexual orientation (heterosexuality, homosexuality, bisexuality and situational sexual behaviour) and a range of other practices among animals other than humans. Related studies have noted diversity in sexed bodies and gendered behaviour, such as intersex and transgender animals.
The study of animal sexuality (and primate sexuality especially) is a rapidly developing field. It used to be believed that only humans and a handful of species performed sexual acts other than for procreation, and that animals' sexuality was instinctive and a simple response to the "right" stimulation (sight, scent). Current understanding is that many species believed monogamous have now been proven to be promiscuous or opportunistic in nature, a wide range of species appear to both masturbate and to use objects as tools to help them do so, in many species animals try to give and get sexual stimulation with others where procreation is not the aim, and homosexual behavior has now been observed among 1,500 species, and in 500 of those it is well documented.[citation needed] A few species have particularly complex sex determination systems. Although two sexes is the official maximum, these complex species could reasonably be said to have 3, 4 or 5 sexually distinct phenotypes. For example:
the clam shrimp Eulimnadia texana has no females, but two types of hermaphrodite and one male phenotype, a system call androdioecy.[8]
harvester ant genus Pogonomyrmex has two types of female and two types of male, with an acknowledged claim to these being considered as constituting at least three distinct sexes,[9] or possibly four.[10]
the reptile tuatara might have four sexes[11]
Coprinus macrorhizus (Pers.) Rea might have three or four sexes[12]
Coprinus lagopus has four sexes[13]
A notable minority view regarding humans has been put forward by Anne Fausto-Sterling, who suggested various disorders of sexual development could be classified into an additional three human sexes.[14][15] Despite mainstream opposition, including the Intersex Society of North America, Fausto-Sterling and others still maintain this view in current publications.
Other species have exhibited evidence of 5 sexes[16]

Humans

Human Male and Female external anatomical features
See Human sexuality for information about sexual activities, sexual sensation, sexual gratification, and sexual intimacy between human beings
In humans, "sex" is often perceived as a dichotomous state or identity for most biological and social purposes - such that a person can only be female or male. But many factors, including one's biology, environment, psychology and social context, have a role in determining how a particular person, and those around them, view their sex. Although the table below shows common differences between males and females, many people do not correspond to "male" or "female" with regard to every criterion. Additionally, about 1 to 1.7 percent of human beings exhibit biological sexual ambiguity to the degree that they cannot be physically classified as exclusively male or female. This is known as intersex. A person with intersex may have biological characteristics of both the male and female sexes.
"Primary" sexual characteristics are typically present at birth and directly involved in reproduction. "Secondary" sexual characteristics typically develop later in life (usually during puberty) and are not directly involved in reproduction. Differences between the sexes are known as sexual dimorphism. At the biological level these differences are usually:
Level
Characteristics
Female
Male
Primary
Sex chromosomes
XX
XY
Gametes
Ova
Spermatozoa
Sex organs
Ovaries
Testes
Predominant Sex hormones
Estrogen and Progesterone
Testosterone
Hormonal Regime
Cyclic during fertility
Tonic (largely unchanging)
Anatomy of internal genitalia
clitoral crura, vagina, uterus, fallopian tubes
corpora cavernosa, urethra, prostate, seminal vesicles
Anatomy of external genitalia
glans clitoris, labia, vulva, clitoral hood, perineal urethra
penis, scrotum, foreskin, fused perineum
Secondary
Skeletal Structure
Relatively shorter,wider in hips
Relatively taller,wider in shoulders,bigger chest
Face
Rounded jaw
Bigger nose bone, brow bone,[17] squarer jaw,facial hair
Body fat and muscle
Relatively more fat
Relatively more muscle[18]
Fat Distribution
More in buttocks, hips and thighs
More in abdomen
Body form development
"Hourglass" shape: 8
"Triangular" shape: ▼
Other
Breasts
Adam's apple and body hair
The relationship between the various levels of biological sexual differentiation is fairly well understood. Many of the biological levels are said to cause, or at least shape, the next level. For example, in most people, the presence of a Y chromosome causes the gonads to become testes, which produce hormones that cause the internal and external genitalia to become male, which in turn lead parents to assign 'male' as the sex of their child (assigned sex), and raise the child as a boy (gender of rearing). However, the degree to which biological and environmental factors contribute to the psychosocial aspects of sexual differentiation, and even the interrelationships between the various psychosocial aspects of differentiation, is less well understood as illustrated by the ongoing nature versus nurture debate. Unfortunately, because of a lack of focus on this area, studies may use data from research not designed to discern the role of sex. One sample of 432 papers publishing the results of gender-related genetics found that only 66.6% of them had set out to deal with the subject before conducting any research and 87.3% used unsound statistics.[19]

Social and psychological issues
Main article: Gender
Gender, in common usage, refers to the differentiation between men and women. It is individual's self-conception or social conception as being male or female, though gender is commonly used interchangeably with sex. Within the social sciences it often refers to specifically social differences, known as gender roles.
Gender discordance
See also: transgender and third gender
Discordance is the term used to describe the extent to which people differ from the usual biological and psychosocial types described above. Some discordances are biological, such as when the sex of the chromosomes (genetic sex) does not match the sex of the external genitalia (anatomic sex), such as in Swyer syndrome, a type of intersex condition. Discordances between the biological and psychosocial levels (such as when the gender identity does not match the anatomic sex) or between the various psychosocial levels (such as when the gender role does not match the gender identity) are even more common, but less well understood.
In gender theory, the term "heteronormativity" refers to the idea that human beings fall into two distinct and complementary categories, male and female; that sexual and marital relations are normal only when between two people of different genders; and that people should follow roles determined by their gender. Instead, some people have sought to define their sexuality and sexual identity in non-polar terms, in the belief that the simple division of all humans into "males" and "females" does not fit their individual conditions. A proponent of this movement away from polar oppositions, Anne Fausto-Sterling, recognized five sexes: male, female, merm (male pseudohermaphrodite), ferm (female pseudohermaphrodite) and herm (true hermaphrodite). Although she was heavily criticized, her idea demonstrates the difficulty and imperfection of the current social responses to these variations.
Social and legal considerations
Main article: Sociology of gender
Forms of legal or social distinction or discrimination based on sex include sex segregation and sexism. Notably, some businesses, public institutions, and laws may provide privileges and services for one sex and not another, or they may require different sexes to be physically separated. Recently, western societies have moved towards greater sexual equality.

Article : Hereditary Hemochromatosis-It can be Treated by: Peter Whittington

Hereditary Hemochromatosis-It can be Treated by: Peter Whittington
Hereditary Hemochromatosis (HH) is the most common genetic disorder of persons of northern European extraction. The most common gene involved in causing Hereditary Hemochromatosis (HH) is the HFE gene. Most patients with hemochromatosis have two copies of the HFE mutation C282Y. In persons of northern European extraction approximately 1 in 10 persons carries one copy of C282Y. Even one copy of C282Y can be associated with too much iron in the liver, high cholesterol, diabetes and the skin disorder porphyria cutanea tarda. Approximately 1 in 200 to 300 persons of northern European extraction carry two copies of C282Y. In some northern European populations eg Ireland, Iceland and Brittany the percentage of persons carrying one copy of C282Y is higher. Predictably countries settled by northern Europeans eg Australia, South Africa and Canada have high rates of hemochromatosis. HH is characterized by excessive absorption of dietary iron and a consequent progressive increase in total body iron stores. Iron accumulates in the parenchymal cells of the liver, the heart, pancreas, anterior pituitary and skin. This accumulation of iron in body tissues causes disease. In severe HH the disorder manifests as potentially life threatening conditions such as septicaemia, cirrhosis of the liver, liver cancer, diabetes, heart failure and heart arrhythmias. Arthritis is common and a severe arthritis involving numerous joints may occur. Ovarian and testicular failure secondary to iron deposition in the anterior pituitary and possibly the hypothalamus may occur. Rarely hypothyroidism may occur. If HH is not treated liver disease may be fatal. The morbidity and mortality of HH can be reduced by early diagnosis and treatment by phlebotomy or blood letting. There is frequently a delay between the onset of symptoms and diagnosis. This is because early symptoms such as fatigue and arthralgia are non-specific. Hereditary Hemochromatosis fits the criteria set by the World Health Organization for population screening for a disease: 1. The homozygous genotype is common and is potentially fatal if not treated 2. The disease has a lengthy latent period with asymptomatic iron accumulation followed by a period of iron overload with reversible organ injury 3. Treatment during the latent period and the period with reversible organ injury restores the life expectancy to normal. (Treatment is safe, effective and cost effective) 4. HH can be detected by measurement of the transferrin saturation (TS). It is very important to make an early diagnosis of HH because patients who have not developed cirrhosis and are treated by phlebotomy have a normal life expectancy. When the diagnosis of hemochromatosis is made it is important to adjust the diet so that too much iron is not being absorbed because of an improper diet. The biggest considerations are not to take medications which contain iron, consume too much alcohol or Vitamin C. The ingestion of black tea has been shown to decrease the absorption of iron. African tea which is becoming popular may contain iron so too much should not be consumed. Don’t take milk thistle which has often been touted as good for the liver as it can cause severe problems in those with hemochromatosis. Don’t eat raw shellfish. They may be contaminated with Vibrio vulnificans which thrives in an iron rich environment. There have been fatalities in the northern hemisphere. Cooking inactivates this organism.

Article : Alternative Cancer Treatments by: Om Prakash

Alternative Cancer Treatments by: Om Prakash
Alternative Cancer Treatments are increasingly being used for treating cancer patients. The treatments are either used a sole therapy or in combination with traditional therapies to cure cancer. These treatments are based on the fact that our own immune system provides the first and best defense against cancer. In alternative cancer treatments vaccines stimulate patient's immune system to recognize and destroy tumor cells. The treatments are customized according to the patient ailing with cancer. Some of the therapies used in an alternative cancer treatment program are: 1. Dendritic Cell Therapy Cancer occurs when the immune system fails and comes across tumor cells. Macrophage or monocyte is an immune cell that comes in contact with th cancerous or precancerous cell. (Pre)cancerous cell signals the macrophage of any unhealthy cell. Macrophage breaks the cell into little pieces with the help of little packets of enzymes. The little pieces are then either moved to another type of immune cell or transformed to what is call a 'Dendritic Cell'. These cells are found in all tissues of the body. The very first dendritic cell discovered occurs throughout the skin and is called a Langerhan's cell. Dendritic cells are helpful in switching on an immune response and these stimulate the T-cells to become active against tumors. Experiments have proved that these dendritic cells with tumor antigens can provide effective response against cancer. It is possible to produce large number of dendritic cells from the circulating blood of cancer patients, find source of tumor antigen and mature them. Dendritic cell therapy is very effective when used with other types of immune therapies. The therapy itself is also useful for patients with high risk of recurrence once the tumor is removed by surgery. 2. Coley Vaccine This Vaccine was developed by William Coley, a surgeon in 1893 at the New York Cancer Hospital. Coley discovered that when his vaccine caused a fever, the cancer shrank and number of immune cells increased dramatically. Usually, fevers are suppressed with medicinal drugs like acetaminophen, aspirin or ibuprofen. But studies have shown that suppressing a fever not only makes the infection worse but also spreads it. Coley recognized the beneficial effects of fever in cancer patients. He also discovered that when he stopped injecting the vaccine too early, the cancer started growing again. Thus, immune cells could be stimulated to fight the cancer for a limited time only. So, he used repeated injections to stimulate the immune system continuously. Though it is called Coley's vaccine, it does not work to prevent an infection. Rather, it induces an immune response. Similarly, Coley's toxins are not toxins though they contain endotoxins and exotoxins. Under the therapy, Coley's toxins are injected into the affected tissues. Injection makes the cancer tissue necrotic which is then removed by drains. Injections are repeatedly given either daily or after every two days, however this varies from person to person. 3. Heat Shock Antigen Cancer Vaccine Immune therapies for cancer stimulate white blood cells to attack cancer cells. Vaccines reprogram patient's immune system to recognize and attack the cells having the cancer fingerprint. Heat shock antigen vaccine captures the particular cancer's 'fingerprint,' which contains unique antigens. The personalized vaccine treats immune systems of cancer patients with little or no side effects. HSAV is made from patients' tumors and heat shock proteins that are produced by patients' white blood cells. Part or all of the cancerous tissue is removed through surgery. White blood cells contain heat shock proteins that are purified and mixed with purified antigens from the tumor. The mixture is filtered and put into vials. The final product is tested for quality and sterility. 4. Cytokines Cancer Vaccine Treatment Cytokines, also known as immune hormones can both enhance and suppress immunity. For cancer treatments, cytokines enhance immunity. FDA has approved two cytokines, interleukin-2 (IL-2) and interferon-alfa 2b, to be used against certain cancers. Combinations of cytokines deliver better results. For example, Interleukin-2 stimulates white blood cells to divide. A very high dose of it will be required if it is used individually. However, that can cause negative side effects. The solution to this can be the use of natural combination produced by white blood cells. By using the combination, the dose of IL-2 can be lowered. Effects of heat shock protein vaccines and dendritic cell vaccines can be enhanced when given with natural cytokine combination. 5. Photodynamic Cancer Therapy Photodynamic therapy is a revolutionary medical technology that uses light to induce reactions in patient's body. The therapy can destroy unwanted tissues without affecting normal tissues. A drug called a photosensitiser is injected into patient's body. The drug makes cells more sensitive to light and eventually destroys the cell. The drug has no effect until exposed to a particular type of light. 6. Immuno-Augmentive Therapy The prime objective of IAT is restoring the immune system to enable it to destroy cancer cells. The therapy restores cancer patient's immune competency so that it can control cancer. Once the natural immune system is restored, patient’s own body becomes capable of treating itself. IAT treatment is not a cure for cancer but a means of restoring natural balance of the system. Om Prakash makes it easy and provides alternative cancer treatment for treating cancer patients. To recieve free part mini-course visit the http://www.immunemedicine.com.

Article : Boost Your Metabolism to Lose Weight

Boost Your Metabolism to Lose Weight
by: Steven Muller



There are a lot of people who would give a lot to increase their metabolism. Having a high level of metabolism enables one to burn fat and lose weight fast with the least amount of exertion. Metabolism is the rate by which the body produces and consumes energy and calories to support life.

There are several factors that affect the metabolism of a person, such as the amount of muscle tissue, the frequency of the meals one consumes, genetics, the digestive system, stress levels, personal diet, and activity levels. Metabolism slows down due to the following: loss of muscle because of not enough physical activity, the tendency of the body to cannibalize its own tissue because there is not enough food energy to sustain it, and the decrease of physical activity that comes naturally with old age.

Here are several ways to fire up one's metabolism:

1. Build up on lean, mean body mass. It is only natural that metabolism decreases along with age, but it is possible to counter the effects. The amount of muscle a person has is a very strong determinant in the ability to burn calories and shed fat. So it goes without saying that exercise is essential. Build strength and resistance by working out at least twice a week, preferably with weights. Do easy exercises in between workouts. Simple tasks such as walking the dog and using the stairs in place of the elevator can already take off calories. The key is to match the amount of eating to the amount of activity one has. Here are some guidelines in getting the right exercise:

For strength training

-Increase the amount of repetitions of a particular exercise.
-Add the level of resistance
-Utilize advance exercise techniques if possible

For cardiovascular training

-Insert intervals between exercises
-Perform cross-training and combine the exercises
-Add up on resistance and speed


2. Eat breakfast. A lot of people are ignoring the fact that breakfast is the most important meal of the day. Surprisingly, the ones who eat breakfast are thinner than the ones who do not. Metabolism can slow down considerably if breakfast is taken during mid-morning or if one waits until the afternoon to eat.

3. Avoid sugar. Sugar enables the body to store fat. It is recommended that a person consumes food that helps sustain an even level of blood-sugar. Additionally, progressive exercise 2-3 times a week should be in order to stabilize blood sugar.

4. Eat spicy foods. Hot cuisine with peppers can increase metabolism.

5. Sleep more. According to research, it is riskier for people who do not get enough sleep to gain weight. Also, muscles are regenerated during the last couple of hours of slumber.

6. Increase water intake. Water flushes out toxins that are produced whenever the body burns fat. Majority of bodily functions involves water, and lack of water causes the body system's operations to decrease its speed, and produces unneeded stress as a result.

7. Detoxify the digestive system. A clean and healthy digestive system not only helps the body to run more efficiently, it also gives you energy and helps you to crave healthier foods. This makes a cleansing program, such as Isagenix 9-Day Cleansing and Fat Burning System, a great way to jump-start a weight loss regimen.

8. Eat smaller meals. It is advisable to consume 4 to 6 small meals that are timed 2 to 3 hours apart.

9. Never skip meals. People tend to skip meals in order to lose weight, which is a big mistake since it slows down metabolism.

10. Plan meals in detail. Always prepare the right amount of food to be consumed at the designated intervals. Do not commit the mistake of eating meals in sporadic patterns.

11. Ditch the stress! Stress, be it physical or emotional, triggers the release of a steroid called cortisol, which decreases metabolism. Also, people tend to eat excessively when stressed.

12. Guzzle up on green tea. It can be used as a substitute for coffee. Tea has the ability to stimulate metabolism, and unlike coffee, it has no undesirable side effects when too much is consumed.

13. Include more energy foods in the diet, such as fruits and vegetables, beans and whole grains.

Achieving the desired body weight is never impossible if one has the determination and patience needed to stabilize the metabolism level, which plays an important role in weight loss. A person needs to realize that eating right and working out is not just a passing fancy, but a way of life. Fighting cravings is hard for most of us. A great help in the quest to eat healthier --and fight those unhealthy cravings-- is a body cleansing program. Visit www.loseweightandcleanse.com for details on Isagenix's 9-Day