The antagonistic effects of the sympathetic and parasympathetic divisions of the autonomic nervous system are known as which type of effects?

• A. Dual innervation effects
• B. Synergistic effects
• C. Isolated effects
• D. Reflexive effects

Answer: (A)

Verified step by step guidance

1. Understand the autonomic nervous system (ANS): The ANS is divided into two main branches, the sympathetic and parasympathetic divisions, which regulate involuntary physiological processes such as heart rate, digestion, and respiratory rate.
2. Learn about antagonistic effects: Antagonistic effects occur when two systems or divisions work in opposition to each other. For example, the sympathetic division typically stimulates 'fight or flight' responses, while the parasympathetic division promotes 'rest and digest' activities.
3. Define dual innervation: Dual innervation refers to the phenomenon where most organs in the body receive input from both the sympathetic and parasympathetic divisions, allowing for precise regulation of physiological functions through their opposing actions.
4. Compare the given options: Analyze the terms provided in the question. 'Dual innervation effects' aligns with the concept of antagonistic effects because it describes the opposing actions of the two divisions. 'Synergistic effects' refer to cooperative actions, which is not applicable here. 'Isolated effects' and 'Reflexive effects' do not describe the interaction between the two divisions.
5. Conclude the reasoning: Based on the definitions and comparisons, the correct term for the antagonistic effects of the sympathetic and parasympathetic divisions is 'Dual innervation effects.'