Question

our nervous system is organized into two broad anatomical divisions: the central nervous system (consisting of the brain and spinal cord) and the peripheral nervous system (PNS). Your PNS is further organized into two functional divisions. If you tap your knee, the signal to act is carried via your ____ to the muscles in your knee. In contrast, the signals that pass via the ____ are involuntary and act primarily to regulate your body's internal environment. This involuntary nerve system is further organized into three divisions. If you need a sudden burst of energy, your ____ is activated to help you act quickly. In contrast, if you are relaxing and conserving energy, then it is your ____ that is primarily in action. The third division is your _____ which helps control the components of the digestive system.

Answer 1

Answer:

If you tap your knee, the signal to act is carried via your somatic nervous system to the muscles in your knee. In contrast, the signals that pass via the autonomic nervous system are involuntary and act primarily to regulate your body's internal environment. This involuntary nerve system is further organized into three divisions. If you need a sudden burst of energy, your sympathetic nervous system is activated to help you act quickly. In contrast, if you are relaxing and conserving energy, then it is your parasympathetic nervous system that is primarily in action. The third division is your enteric nervous system which helps control the components of the digestive system.

Explanation:

Peripheral nervous system (PNS) is the nervous system that contains nerves and ganglia outside the central nervous system (CNS). PNS is divided into:

• somatic (voluntary) nervous system-controls the movements of the skeletal muscles
• autonomic (involuntary) nervous system-controls the smooth muscles and glands and thus it is the regulator of the major body functions. It is subdivided into tree groups:

1. sympathetic ("fight and flight") system-responsible for stressful and active situations (but also in normal conditions)
2. parasympathetic ("rest and digest") system-opposite to sympathetic, responsible for the maintenance of body's activities at rest.
3. enteric nervous system-controls the function of the gastrointestinal tract.