Being a Teen (6 page)

Scrotum

The soft pouch of wrinkly skin that you see on either side and slightly behind your penis is the scrotum, which is divided inside into two pouches. Each pouch holds one testis. Many people refer to the
scrotum
and
testes
altogether as the
“testicles”
or “balls.”

In adult men, usually the left side of the testicles hangs lower, and the testicle on the right is larger. This helps keep the
testes from rubbing against or squishing each other while a man is walking or running.

Testes

You can feel the testes inside your scrotum. They are rather hard, sort of like a grape. You can roll them around. Testes are made up of a number of compartments, inside of which are tiny tubes, all intertwined. That is where the hormone
testosterone
is made. Testosterone helps produce sperm and also causes many of the pubertal changes to your body, such as facial hair, deepening voice, and muscle growth.

Because the sperm inside the testes are sensitive to heat, they must be kept several degrees cooler than the temperature of the body or they will die. So if the testes get too warm, the scrotum hangs farther down from the body to help cool them off. If they get too cold, muscles in the scrotum pull them
closer to the body to warm up. This is why when a boy or man swims in cold water, he can feel his scrotum contract.

The scrotum also tightens up:

• When the penis is erect.

• If a male feels frightened or nervous. Although they’re really important, the testes have nothing around them to protect them. Getting closer to the body makes them safer.

In
Chapter 7
, I will go into questions about penis size and other such matters.

Anus

In both females and males, the
anus
¹²
is the small entrance to the
rectum
through which bowel movements (also called
feces,
¹³
stool,
or “poop”) leave the body. Unlike the female body, which has three openings from front to back (the urethra, the vagina, and the anus), the male body has two openings, the one at the penile tip—the urethra—and the other at the anus.

Ejaculation

Once you begin puberty, you start making sperm. When a man is sexually excited and ready to ejaculate, the
prostate gland
¹⁴
begins a series of rapid contractions that force the sperm
from the testicles through the seminal vesicle, where it mixes with other fluids to form semen (also called “cum” or “jism” or “jiz”), a whitish fluid full of nutrients and sugar.

At different times, the semen might be any color from white to clear, and it can be thick or thin.
Ejaculation
¹⁵
is when the muscles pump the semen down the hollow urethral tube and out the end of the penis, releasing about a teaspoon of fluid. The speed of an ejaculation can vary from dribbling to shooting out semen really fast. All of this is normal. But no matter how it comes out, semen is always filled with 300 to 500 million sperm, any one of which can make a female pregnant if intercourse occurs. By the way, an
erection
¹⁶
can (but doesn’t have to) end with ejaculation. Most boys have their first experience of ejaculation while
masturbating
(rubbing, pulling, or stroking the penis and making it stiff) or having a wet dream. I explain more about masturbation in
Chapter 10
.

Pre-ejaculate
is a fluid that oozes out of the penis before ejaculation. It does not contain sperm on its own but it may include a small amount of sperm if a previous ejaculation has occurred recently. This means that, with sexual intercourse, pregnancy can sometimes result from pre-ejaculate fluid.

Sexual Intercourse and Conception

Sexual intercourse is how a man and a woman can make a baby. It can be a beautiful, exciting, loving act that gives pleasure to both partners, even if they are not planning to make a baby.

This is how sexual intercourse can lead to conception: The man’s erect penis goes inside the woman’s
vagina,
which, if the woman is excited enough, has become lubricated and more
slippery, allowing the penis to slide in easily. After a period of lovemaking, during which the penis moves in and out of the vagina, the man ejaculates, sending millions of sperm swimming up the vagina and into the uterus. If just one of those millions of sperm connects with the woman’s
ovum,
or egg, a baby begins to grow.

A girl is born with all of her eggs. Once a month, in an adult woman, an egg leaves the ovary and goes into the fallopian tube.
This process is called
ovulation.
¹⁷
The ripe egg is swept down the tube by tiny hairs as it heads for the uterus. If a sperm has reached the uterus and enters the egg within twenty-four hours of when the egg left the ovary,
fertilization
¹⁸
takes place, the egg becomes planted in the uterus, and a fetus will begin to grow.

If the egg is not fertilized, it breaks down and flows out of the woman’s body, together with blood and tissue. This is called
menstruation
¹⁹
or “having a period.”

Reasons to See a Doctor

Here are some reasons you’d need to ask a grown-up to make an appointment for you with a doctor:

• You’re eight and a half to nine years old and have already started puberty, or you’re fourteen to fifteen and haven’t experienced any hormonal changes such as acne, a growth spurt, pubic hair, or body odor.

• You can’t fully retract your foreskin (the skin covering the end of your penis, for those not circumcised), and it causes pain or discomfort.

•
You injure one or both testes. This will hurt a lot, but wait an hour or so. If the pain continues or if you become swollen or bruised, you need to be checked.

• You have a sore (painful or not), tender spot, blister, rash, or wart anywhere on your genitals that doesn’t go away in a day or two.

• You have a scaly, itchy rash. First buy an antifungal cream, which can prevent or cure fungus. If it doesn’t clear up, you need to be checked.

• You feel pain anywhere in your genitals or lower abdomen. Sudden, severe pain in your testicles, especially with blood in your urine or nausea, is a potential emergency and requires an emergency doctor visit.

•
You have a painful erection, not caused by sexual stimulation, for four hours or more. This is called priapism and is an emergency.

• You feel a lump anywhere in or on your genitals.

• You have any kind of unusual discharge coming out of your penis.

• You see any kind of change in your urine.

• You feel burning or pain when you urinate or have to do it often.

• You have a bad smell under your foreskin.

• You have persistent redness on your face from shaving irritation or cuts, or you have infected ingrown hairs.

• You’re bothered by persistent questions or concerns about your body.