The great changes in the structure and function of the human body in adolescence are caused by hormones. During adolescence, a part of the brain, the hypothalamus and pituitary gland, secretes almost the same hormones as adults. It leads to a series of amazing changes in your body: clothes are used up quickly, food intake suddenly increases, you suddenly find yourself running fast and jumping high, and one day you suddenly find yourself thinking about something, and there is a secret space in your heart that you don't want anyone to enter ... These changes are happening rapidly, just like the undercurrent on the seabed-do you feel it? In fact, it is precisely the secretion of hormones such as auxin, thyrotropin and gonadotropin that has reached a new level. Among them, auxin directly acts on tissues and cells of the whole body, which can increase the volume and quantity of cells and promote individual growth. The increase of thyroid hormone level caused by the increase of thyrotropin secretion can enhance the metabolic process of the whole body. Gonadotropin stimulates ovarian follicle development and testicular sperm production.

Second, the gender differences in adolescent posture

There are obvious gender differences in puberty physical development, sudden increase and key parts of change. The development level of women aged 9 ~ 10 is higher than that of men of the same age, and the development level index of men around 15 is higher than that of women of the same age. By the age of 18, men have reached a higher level than women in the absolute values of the above four indicators. In the end, men are taller, wider in shoulders, fuller in body and wider in buttocks.

Sooner or later, it will also cause changes in body shape. Early development stops early, and adulthood may be shorter and fatter than later development. Therefore, adults often form a body shape with narrow shoulders and wide pelvis. In the later stage of development, it often grows into a slender type with wide fertility and narrow pelvis. Therefore, during this period, we should pay special attention to reasonable diet and strengthen physical exercise.

Third, the physiological function is gradually enhanced.

The weight and volume of the brain are close to those of pre-adolescent adults, and the differentiation function of brain cells reaches the adult level. The improvement of this quality provides a material basis for individuals to adapt to the complex changes in the external world. At the same time, due to more and more social practice, the internal structure and function of the brain are constantly differentiated and developing rapidly. These changes have greatly improved teenagers' memory, understanding and thinking ability. At the same time, the heart grows rapidly, the myocardium thickens and the heart function improves significantly, which is very important to adapt to the increase of various activities.