Know Your Body

Sexual Anatomy


It might not be as obvious as your other sexual parts, but your most erotic organ is actually found above the waist. In fact, it’s even located above the shoulders.

Usually when we think of our sexual organs we think about our genitals. But it is important to keep in mind that the most important sexual organ that we have is the brain.

How we respond sexually is dependent on a wide variety of biological, psychological, and environmental factors. All of these influences are controlled by or filtered though your brain.

Without your brain, there would be no feelings of sexual desire. You may not be consciously controlling it, but it’s the brain that sends the signal for your vagina to lubricate or your penis to become erect when you are aroused and it’s your brain that responds to having your clitoris stimulated and sends the message to your body to trigger an orgasm.

Your brain is also responsible for triggering the secretion of hormones into the bloodstream, which contribute to sexual arousal and desire.

Just as important is the fact that all of our life experiences, everything we have learned, including our attitudes and emotions related to sexuality are absorbed by our brains and interact with our biology to shape who we are as a sexual person.

So, while penises and vaginas are obviously important, keep in mind that the brain is the most important sexual organ of all.


At the northernmost point of the vagina, far south of the bellybutton, lives one of the most important physical elements of a woman’s orgasm.

For most women, the clitoris is an important source of sexual pleasure. It’s located just above the urethral opening at the upper part of the vagina.

There are three parts of the clitoris that you can see: the glans, sometimes called the tip or head; the shaft; and the hood. When a woman becomes sexually aroused the shaft (usually about 2.5 centimeters long and about ½ a centimeter wide although the size of the clitoris varies from one woman to another) swells, the hood pulls back and the glans (often about the size of a pea) becomes hard.

Packed with nerve endings, the clitoral glans is the most sensitive part of a woman’s body. Stroking or rubbing the clitoral area is the way most women have an orgasm.

Although only the glans, hood and shaft of the clitoris are visible, the clitoral structure extends into the body including along either side of the vagina.


The vagina has become the epitome of female sexuality, but how much do you really know about it?

Because the vagina plays a central role in human reproduction, it’s what people often think of first when it comes to the female genitals.

The vagina is typically 8 to 10 centimeters long but is very elastic (elastic enough to handle the birth of a child). The vagina expands somewhat and lubricates when a women becomes sexually aroused.

In general, the most sensitive part of the vagina is the outer third where the most nerve endings are located. The deeper two-thirds have far fewer nerve endings and so this area of the vagina is less sensitive.


If you find it, you may enjoy it.

There has been a lot of controversy about the female G-spot and whether it exists or not.

Based on surveys asking about the G-spot it looks like some women believe they have a G-spot and have experienced sexual pleasure when it has been touched, and for some women there does not seem to be a specific G-spot area that is especially sensitive compared to other parts.

The G-spot is located about 2.5 to 5 centimeters inside the vagina on the upper wall. When stimulated, usually by fingers, a dildo or vibrator, or penis, the G-spot swells from about the size of a dime to about the size of a quarter or loonie.

When it’s first stimulated the women sometimes feels like she needs to urinate but the sensation can change to sexual pleasure that leads to orgasm. For some women, when they have a G-spot induced orgasm a clear fluid comes out of the urethra, sometimes called female ejaculation. For some it’s just a small amount and for others it’s quite bit.

The bottom line about the G-spot is that if you have discovered that you have one, that’s normal. If you don’t seem to have one, that’s normal too.


Breasts have become incredibly sexualized in our culture, to the point where we begin to confuse size with worth. But really, let’s enjoy them as they are.

In some cultures, breasts have very little erotic significance: they are seen mainly as a way of feeding babies. There’s no doubt that in Western culture, female breasts are viewed very much in a sexual context.

The fact is that breasts are a little bit like penises: their size has nothing to do with the ability to give or receive pleasure or to have an enjoyable relationship. Small, big, or somewhere in-between, breasts can be a positive, pleasurable part of your sexuality – but it’s not the size that counts.

The breasts and nipples can definitely be an erogenous zone for women, and some men. Many women, for example, find it pleasurable and arousing to have their breasts and nipples caressed.


Whether or not you choose to include the anus in your sexual practices, there are a few things you should know.

Technically speaking, the anus is not a sex organ in that it’s not involved in reproduction. But for some people, it definitely is an erogenous zone. It’s a source of sexual pleasure for some.

Many people assume that anal penetration is something that only gay men do but it’s estimated that among adults 25-44 years of age, 40% of men and 35% of women have tried anal sex.1 Some people have no interest in anal sex as a sexual activity and that’s ok.

If you’re interested in anal sex there are a few things that are very important to keep in mind. The anus is much less elastic and stretchable than the vagina. In other words, a penis in the anus is likely to be a much tighter fit than a penis in the vagina. So, it is strongly recommended that plenty of lubrication be used to make the activity more comfortable, especially for the receptive partner, and to avoid the tearing of tissue in the anal canal.

1Mosher, W, Chandra, A and Jones, J (2005). Sexual Behaviour and Selected Health Measures: Men and Women 15-44 Years of Age, United States, 2002. Advance data from Vital and Health Statistics, no 362. US Department of Health and Human Services.


As a society, much of what is said about the penis is more myth than fact. How much do you know?

Although the penis seems like a simple thing, lots of people don’t understand its basic anatomy. It’s not a muscle and has no bones. So what is it exactly?

The main part of the penis, often called the shaft, contains three cylinders that run parallel to the urethra – the tube urine and semen pass through.

The two cylinders on the topside of the penis are called the corpora cavernosa and the single cylinder on the bottom side is called the corpus spongiosum. All three cylinders contain a spongy tissue that fill with blood when a man is aroused, resulting in an erection.

The most sensitive part of the penis is the head, sometimes referred to as the glans. For men who haven’t been circumcised, the head is covered with a retractable layer of skin called the foreskin.

Many men are concerned about penis size and assume that bigger is better. In some ways, penis size is like breast size: some are a little bigger and some are a little smaller. But at the end of the day it doesn’t really matter. Penis size has very little to do with a man’s ability to please a partner sexually.

Physiologically speaking, penis size makes no difference. For example, a woman’s vagina is quite elastic so unless a man has an extremely large penis, a woman isn’t going to feel a difference during intercourse. If the penis is so large that she does notice a difference it’s probably because it’s making her uncomfortable. For the record, the average length of a human penis is about 9.0 – 10.0 centimeters (2.5-3.9 inches) when flaccid and about 12.8 – 15.0 centimeters (5.0-5.9 inches) when erect. In terms of girth, the average penis is about 10.0-10.5 centimeters (3.9-4.1 inches) around.