Puberty and Adolescence
Jessica Harwood
Douglas Wilkin, Ph.D.
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AUTHORS
Jessica Harwood
Douglas Wilkin, Ph.D.
EDITOR
Douglas Wilkin, Ph.D.
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Printed: August 13, 2015
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C HAPTER
Chapter 1. Puberty and Adolescence
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Puberty and Adolescence
• Define puberty and adolescence.
• Outline changes that occur during puberty and adolescence.
How do you know you are entering puberty?
The first signs of puberty appear at different times for different people. A boy might realize he’s reached puberty
when he starts needing to shave. A girl, on the other hand, starts getting her menstrual period during puberty.
Puberty and Adolescence
Puberty is the stage of life when a child becomes sexually mature. Puberty lasts from about 12 to 18 years of age
in boys and from about 10 to 16 years of age in girls. The age when puberty begins is different from one child to
another. Children that begin puberty much earlier or later than their peers may feel self-conscious. They may also
worry that something is wrong with them. Usually, an early or late puberty is perfectly normal.
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In boys, puberty begins when the pituitary gland tells the testes to secrete testosterone. Testosterone causes the
following to happen:
1.
2.
3.
4.
The penis and testes grow.
The testes start making sperm.
Pubic and facial hair grow.
The shoulders broaden, and the voice becomes deeper.
In girls, puberty begins when the pituitary gland tells the ovaries to secrete estrogen. Estrogen causes the following
to happen:
1.
2.
3.
4.
5.
The uterus and ovaries grow.
The ovaries start releasing eggs.
The menstrual cycle begins.
Pubic hair grows.
The hips widen, and the breasts develop.
Boys and girls are close to the same height during childhood. In both boys and girls, growth in height and weight
is very fast during puberty. But boys grow faster than girls during puberty. Their period of fast growth also lasts
longer. By the end of puberty, boys are an average of 10 centimeters (4 inches) taller than girls.
Adolescence
Adolescence is the period of life between the start of puberty and the beginning of adulthood. Adolescence includes
the physical changes of puberty. It also includes many other changes. During adolescence:
• Teenagers develop new thinking abilities. For example, they can think about abstract ideas, such as freedom.
They are also better at thinking logically. They are usually better at solving problems as well.
• Teenagers try to establish a sense of who they are as individuals. They may try to become more independent
from their parents. Most teens also have emotional ups and downs. This is partly due to changing hormone
levels.
• Teenagers usually spend much more time with peers than with family members.
FIGURE 1.1
These teens are good friends. Like most
teens, they spend more time with one another than they do with family members.
These teens are volunteering at a charity
event. What do you enjoy doing with your
friends?
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Chapter 1. Puberty and Adolescence
Summary
• A child becomes sexually mature during puberty.
• Adolescence includes the physical changes of puberty among other changes.
Explore More
Use the resource below to answer the questions that follow.
• Puberty at http://www.youtube.com/watch?v=TRyOcLSJDzk (3:04)
MEDIA
Click image to the left or use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/57537
1.
2.
3.
4.
What is puberty? Are the first changes of puberty visible? What are they?
What is the average age that girls start puberty? When do physical changes usually appear?
What is the average age that boys start puberty? When do physical changes usually appear?
What kinds of non-physical changes may occur during puberty?
Review
1.
2.
3.
4.
5.
When does puberty occur in boys? In girls?
What changes occur during puberty in boys?
What changes occur during puberty in girls?
What is adolescence?
Along with physical changes, what else changes during adolescence?
References
1. Image copyright mangostock, 2014. Teenagers often spend more time with peers than with family members
. Used under license from Shutterstock.com
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