If a person needs to run away from a dangerous situation, the nervous system sends blood to the persons extremities to prepare him or her for taking off.

The answer to this question is sympathetic nervous system.

 Sympathetic nervous system functions when a stressor is activated. In the sample question, the person was in a dangerous situation that makes the sympathetic nervous system activated by making the person sweating. When the sympathetic nervous system is activated the adrenal gland also works by releasing epinephrine. 

The sympathetic nervous system gets activated in case of stressful or dangerous conditions. In such situations, the hormones rush to boost the body’s awareness and heart rate by enhancing blood flow towards the muscles.

Further Explanation:

The part of the autonomous nervous system which performs involuntary functions is called the sympathetic nervous system. With unconscious direction, this part of the nervous system controls the blood pressure, heart rate, body temperature, digestion, and sweating. The researchers have suggested that neurons or nerve cells are responsible for such physical reactions that act through cardiac muscle, skeletal muscle, and gland secretions. This system enables living beings to become immediately alert and react without giving a second thought.

The body’s involuntary responses which might be the outcome of dangerous situations are directed by the sympathetic nervous system. A rapid increase in hormone concentration results in increased heart rate and alerts the body. This is accompanied by bulk flow of blood into the muscles to perform their respective function properly. The rate of breathing increases which causes the discharge of fresh oxygen into the brain and also results in glucose infusion into the blood which further boosts energy levels. Such a response takes place in a short span of time that a person does not even realize if it has happened. For example, a person quickly jumps off from the path as soon as he/she realizes a tree falling upon him/her.

Here, when a person detects a dangerous situation, the sympathetic nervous system is activated. On activation, the system governs the body for a quick response to avoid the stressful condition. This is done as the adrenal gland is stimulated by the sympathetic nervous system to release epinephrine. The hormonal release causes sudden changes in the body such as sweating or increased heart rate which further increases blood flow for the muscles to get activated to show the immediate response.

Learn More:

1. Learn more about the effects of vigorous exercise on cardiorespiratory system

2. Learn more about the structure of epithelium and connective tissue

3. Learn more about the secondary function of the lymphatic system

Answer Details:

Grade: High School

Chapter: Sympathetic Nervous System

Subject: Biology

Keywords:

Autonomous nervous system, sympathetic nervous system, involuntary nervous system, blood pressure, heart rate, body temperature, stressful condition, sweating.

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.