Question

Name the hormone which stimulates the entire sympathetic nervous system.

Answer 1

Hint:Hormones are chemical messengers which are directly secreted into the blood, taking them to the body's organs and tissues to perform their functions. There are several hormone types that work on various aspects of body functions and processes. It is also known as the emergency hormone which increases the metabolic rate and allows heart and brain blood vessels to dilate. It also increases the metabolism of fat and more energy is thus synthesized.

Complete answer:Part of the autonomic nervous system (ANS), which also comprises the parasympathetic nervous system (PNS), is the sympathetic nervous system (SNS).
Epinephrine, although it also releases some norepinephrine, is the primary hormone secreted by the adrenal medulla. The rate of secretion by the adrenal medulla of catecholamines is largely controlled by the same mechanisms which control sympathetic nervous activity.
The sympathetic nervous system releases the hormone most commonly referred to as the fight or flight reaction called adrenaline. The alarm is then transmitted to the sympathetic nervous system by the hypothalamus and the signal continues to the adrenal glands, which then generate epinephrine, better known as adrenaline. The profuse sweating, fast heartbeat, and quick breaths we associate with stress are caused by this hormone
Adrenaline is a hormone, neurotransmitter, and drug often referred to as epinephrine. Both the adrenal glands and certain nerves usually contain adrenaline. By the blood flow to muscles, heart output, pupil dilation response, and blood sugar level play an important role in the fight-or-flight response. Hence the hormone Adrenaline activates the Sympathetic nervous system.
So, 'Adrenaline' stimulates the entire SNS is the right answer.

Note:Norepinephrine is a naturally occurring chemical in the body that serves as a neurotransmitter (a chemical that sends messages between nerve cells) and a stress hormone. As a stress hormone, it is released into the blood when the brain perceives that a traumatic event has happened.