Which division of the autonomic nervous system would you expect to be activated if a person heard an intruder at the front door?
a. Parasympathetic
b. Sympathetic
c. Enteric

Verified step by step guidance

1. Understand the autonomic nervous system (ANS): The ANS is divided into three divisions: the sympathetic, parasympathetic, and enteric systems. Each division has specific roles in regulating involuntary physiological functions.
2. Review the role of the sympathetic division: The sympathetic nervous system is responsible for the 'fight or flight' response, which prepares the body to respond to perceived threats or emergencies by increasing heart rate, dilating pupils, and redirecting blood flow to muscles.
3. Review the role of the parasympathetic division: The parasympathetic nervous system is responsible for the 'rest and digest' state, which promotes relaxation, digestion, and energy conservation.
4. Review the role of the enteric division: The enteric nervous system primarily controls gastrointestinal functions and operates independently of the 'fight or flight' or 'rest and digest' responses.
5. Determine the correct division: Hearing an intruder at the front door would likely activate the sympathetic division, as this situation involves a potential threat that requires a 'fight or flight' response.

Key Concepts

Autonomic Nervous System

The autonomic nervous system (ANS) is a component of the peripheral nervous system that regulates involuntary physiological functions, including heart rate, blood pressure, respiration, and digestion. It is divided into three main divisions: sympathetic, parasympathetic, and enteric, each playing distinct roles in maintaining homeostasis and responding to stressors.

Sympathetic Nervous System

The sympathetic nervous system is responsible for the body's 'fight or flight' response during stressful situations. When activated, it prepares the body for rapid action by increasing heart rate, dilating airways, and redirecting blood flow to muscles, which would be crucial if a person perceives a threat, such as an intruder.

Parasympathetic Nervous System

The parasympathetic nervous system promotes the 'rest and digest' state, counteracting the effects of the sympathetic nervous system. It conserves energy by slowing the heart rate, increasing intestinal and gland activity, and relaxing sphincter muscles, which is more active during calm, non-stressful situations.