When puberty starts, your brain sends signals to certain parts of the body to start growing and changing. These signals are called hormones. Hormones also can cause emotional changes. During your teen years, hormones can cause you to have strong feelings, including sexual feelings. You may have these feelings for someone of the other sex or the same sex.
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You and Your Sexuality (Especially for Teens)
How much will my teen grow?
Reproduction is the process by which organisms make more organisms like themselves. But even though the reproductive system is essential to keeping a species alive, unlike other body systems, it's not essential to keeping an individual alive. In the human reproductive process, two kinds of sex cells, or gametes GAH-meetz , are involved.
The teenage years are also called adolescence. During this time, teens will see the greatest amount of growth in height and weight. Adolescence is a time for growth spurts and puberty changes. A teenager may grow several inches in several months followed by a period of very slow growth. Then they may have another growth spurt. Changes with puberty may happen slowly.