Boys typically begin puberty later than girls do, somewhere between the ages of 12-16. Changes start happening once the testicles start producing large amounts of testosterone.
Guys usually experience rapid body growth in a short period of time. Hands, feet, legs, and arms all grow and shoulders will broaden. Muscles also grow during this time. Guys will begin to grow hair on their face, legs, underarms, and sometimes on their chest. Some decide to shave their face.
Guys will also notice that their skin becomes oilier during puberty. He may also notice that he sweats more than he used to. This is to be expected. Taking daily showers and making sure that the face is kept clean are important. However, even with careful attention to hygiene, acne may develop. Acne commonly occurs on the face, back and chest. Many teenagers experience acne in one form or another throughout puberty. Note that washing the face too often can also aggravate the skin, so if acne is a problem it is recommended to visit a dermatologist.
A guy’s voice will also change during puberty. A boy may notice that his voice begins to crack. Hitting high notes may become difficult if not impossible. The voice will eventually become much deeper.
The parts of the body that make up a guy's reproductive system are more than just the penis. The reproductive organs that you can see are:
Penis: the tube-like sexual organ on the outside of the male body
Scrotum: sac of skin that holds the testicles and rests under the penis
Testicles: two small organs located in the scrotum that produce sperm
There are also reproductive organs that are not visible, because they are inside the body. For boys these include:
Prostate Gland: small walnut-sized gland located inside the male body, between the penis/testicles and the anus. It produces some of the fluid that makes up semen
Vas deferens tube: tubes that carry semen and sperm
Sperm ducts: glands that produce some of the fluid that makes up semen.
The penis is made up of two parts, the head and the shaft. The head is the tip of the penis and it contains many nerve endings that make it very sensitive. The shaft is the "body" of the penis and is less sensitive than the head. When the penis is soft, the skin of the penis is loose and wrinkly.
The penis is made up of spongy tissue that can fill with blood. When this happens, the penis becomes larger and harder.
Inside the penis is the urethra, a that tube which transports both urine and semen.
Starting in puberty, millions of male sex cells are made in the testicles every day. These are called sperm. If a sperm meet an egg pregnancy can result. Sperm mixes with other fluids and becomes semen. Semen is a whitish fluid that comes out of the male’s body through the penis at the point of ejaculation.
Erections do not always occur on command, especially during puberty. They may occur when least expected. Although many guys feel like everyone is watching them when this happens, this is usually not the case and there is no need for embarrassment. Erections only mean that the penis is hard; they do not mean that a guy is horny or thinking about sex. In fact, during puberty erections often have nothing to do sex at all. At times, boys may also experience something called "wet dreams". While sleeping, a boy’s penis will become hard and ejaculate. This is perfectly normal and usually stops happening as puberty ends.
It can also happen that a guy cannot have an erection when he wants one. This can be a very common occurrence. There are many reasons that this happen. It may be related to a physical or an emotional issue. Alcohol and some drug use can interfere with a male getting an erection. If a guy has a problem getting or maintaining an erection, he might consider talking to someone he trusts and/or seeing a medical professional.
Guys might experience “blue balls” a term that describes soreness or pain felt in the testicles. It can happen when a guy has an erection for a long time and doesn’t ejaculate. Although the sensation may be slightly uncomfortable, there is no need for concern, as there is no damage being done to the penis or testicles. This pain can be alleviated by masturbating to orgasm.
Penises are many different shapes and sizes. All are normal. As a boy grows and changes, his scrotum, testicles, and penis will grow. Sometimes the scrotum and testicles grow first which can make the penis look smaller, but this is normal and the penis will grow later. Generally, a penis will reach its adult size by the time a guy is 18.
There is no “normal” sized penis. Every body is different and there are countless shapes and sizes. Some might be longer and some might be thinner. Many guys worry about the size of their penis, but the fact is, everybody is different.