Question

1. Distinguish between the sympathetic and the parasympathetic divisions of the autonomic nervous system. For each division, provide an example of a situation in which the division would become active. Describe the effects on several bodily processes of the activity of each division.

Answer 1

The automatic nervous system (that controls involuntary functions of body) is divided into sympathetic and parasympathetic nervous system.

Sympathetic nervous system is responsible for controlling fight or flight responses in a state of perceived threat or sudden excitement. Whereas parasympathetic nervous system is responsible for controlling the rest and digest function of body.

For example, when an individual is caught up in a threatening or exciting situation, sympathetic nervous system is activated which prepares the body for sudden action (to run, to shout or to attack).  

Conversely, when an individual is calm and relaxed and doesn't perceive any danger or excitement, the parasympathetic nervous system is activated which prepares the body for rest and digestion.

When sympathetic nervous system is activated it affects several body processes that include the following

1) Speeds up heart

2) Increases respiration

3) dilation of pupils

4) inhibition of salivation

5) Relaxation of lunges and bladder

6) inhibition of fuctions of stomach, gallbladder and intestines

7) increases kidney secretions.

8) Relaxation of muscles

When parasympathetic nervous system is activated it affects following body processes:

1) Slows down heart rate

2) Decreases respiration

3) Compression of pupils

4) Stimulation of saliva

5) Compression of lungs

6) Stimulation of functions of stomach (especially digestion), gallbladder and intestines.

7) Contraction of bladder

8) Contraction of muscles

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