The sympathetic and vagus nerves belong to the autonomic nervous system. They regulate the work of not only the heart, but also the blood vessels. Thus, the sympathetic nerve not only enhances the activity of the heart, but also narrows the arterial vessels that extend from the heart. As a result, the pressure on the walls of arterial vessels increases. But if it reaches a critical level, the action of the vagus nerve is enhanced, which not only weakens the activity of the heart, but also widens the lumen of the arterial vessels. This leads to a decrease in pressure. As a result, in a healthy person, the level of blood pressure is maintained within certain limits. If it becomes lower than normal, the action of the sympathetic nerves, which will correct the situation, will intensify.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.