Erection Of The Penis
What is the process behind your penis going from flaccid to erect?
Your penis is normally in a flaccid (limp) state. It is flaccid because it simply wouldn’t be practical to have a constant erect penis.
It is kept flaccid because something called the smooth muscles in your penis are contracting. These muscles are constantly squeezing and contracting on the tissues and blood vessels in your penis, so that almost no blood is allowed to enter your penis.
With almost no blood in your penis, it will be limp or flaccid.
This all changes when you are sexually stimulated. This could be by a touch, a sexual thought, etc.
A Brief Anatomy Of The Penis
Let’s try to understand the main components of the penis and how they work.
These three structures lay parallel to each other, and run from the base of your penis, all the way to the glans (the head of your penis).
The parts of the penis that are responsible for making the penis hard are the corpora cavernosa.
During an erection, these two chambers are filled with so much blood that the pressure increases substantially.
This provides the stiffness of the erection.
This can simplistically be compared to filling a bike tire with air: as the inner tube becomes filled with air, pressure increases, the outer rubber provides resistance and the tire becomes firm and hard.
Also, the wall between the two units of the corpora cavernosa has a number of openings that let blood flow freely between the two sides so that the pressure is similar in both of these chambers.
Let’s dig into the details of how your penis becomes erect.
The Process Of A Penis Erection
During his investigation, Da Vinci also wrote, “The penis does not obey the order of its master, who tries to erect or shrink it at will, whereas instead the penis erects freely while its master is asleep. The penis must be said to have its own mind, by any stretch of the imagination.”
So the penis fills with blood to become erect, but why is it flaccid most of the time?
The reason a penis is normally kept in a flaccid state, is because the smooth muscles inside the erectile structures of the penis are contracted.
These contracted muscles squeeze around the tiny arteries inside the erectile tissue, allowing only tiny amounts of blood to flow into the penis. This bloodflow is simply for penis maintenance and to provide nutrients and other essential components.
And as long as this blood pressure is adequately low, blood will not flow into the penis and the penis will remain flaccid.
This changes when a man gets ‘turned on’, or has some form of sexual stimulation, such as a sexual thought or is being touched sensually.
Levels of free calcium, the chemical whose job it is to keep the smooth muscles in the penis contracted, are decreased. The smooth muscles then relax and give up the tight grip on tissues and blood vessels in the penis, and blood is allowed to flow into the penis.
As blood enters the corpora cavernosa, these chambers starts getting filled up. As they get filled up, pressure is increasing, blood is then pushing on the tunica albuginea, firmness and pressure continues to build, and the penis becomes erect.
The Detailed Explanation Of A Penis Erection
Your penis is normally flaccid. But why?
And only a small amount of blood is allowed to the penis for nutritional and maintenance purposes.
But how exactly is the flaccid state maintained?
So how do you get an erection?
The process for a penis to become erect is normally started when a man has a sexual thought or some form of sexual stimulation. This stimulation could for instance be a kiss or a touch.
As the tunica albuginea stretches, it builds up pressure and firmness.
This pressure also compresses the veins at the bottom of the penis where blood would normally flow out.
Or put differently, the pressure makes the tunica albuginea block the veins that channel blood away from the corpora cavernosa. This traps blood within the penis, the pressure increases and the penis becomes erect.
The continuation of the erection is also made possible by the tunica albuginea which acts as a gatekeeper by maintaining the pressure and pressing down on the veins that hold blood off from flowing out of the penis.
And before ending this section, I just wanted to add a few words on testosterone.
Because nitric oxide synthase is highly dependent on testosterone to function properly. If there is an inadequate level of testosterone, this will normally cause these enzymes to produce less nitric oxide.
How Does Your Erection End?
When a man has had an orgasm, or sexual stimulation is ceased, the erection will normally fade.
Blood is then forced out of the penis by the contracting muscles, and the erection ends.
How Do Viagra, Cialis And Levitra Produce Erections?
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