The human body undergoes several changes during adolescence. These changes mark the onset of puberty. The most important change which marks puberty is that boys and girls become capable of reproduction. Puberty ends when an adolescent reaches reproductive maturity. The onset of puberty brings about growth of the reproductive organs. Hair grow at various places on the body. Breasts develop in girls and facial hair (moustache and beard) appear in boys. Voice of boys becomes hoarse as voice box enlarges during adolescence.

The change that occurs in a body due to physical, emotional or psychological strain is known as stress. It is the state of too much pressure. It generally takes place when we feel and think that we are unable to manage a particular situation. Due to stress blood pressure, heart rate and blood sugar levels increases. Laughing, music, meditation, yoga, talking to your friends, time management are few techniques or therapies for stress management.