Sympathetic Division

Definition

The sympathetic division is part of the autonomic nervous system responsible for the body's 'fight or flight' response, preparing the body for stressful or emergency situations. This division increases heart rate, dilates airways, and inhibits digestive activities, effectively redirecting energy to essential functions during a crisis. By doing so, it alters physiological processes to enhance survival and immediate physical performance.

5 Must Know Facts For Your Next Test

1. The sympathetic division primarily uses neurotransmitters such as norepinephrine to facilitate rapid responses in the body during stress.
2. This division activates the adrenal glands, leading to increased production of adrenaline (epinephrine), which further enhances the fight or flight response.
3. During sympathetic activation, blood flow is redirected from the digestive organs to the muscles and vital organs to prepare for physical exertion.
4. Sympathetic stimulation results in decreased peristalsis and secretion in the digestive system, slowing down digestion during times of stress.
5. The sympathetic division works in tandem with the parasympathetic division to maintain a balance in bodily functions, switching between states of alertness and relaxation as needed.

Review Questions

• How does the sympathetic division affect digestive processes during a stress response?
  • During a stress response, the sympathetic division inhibits digestive processes by decreasing peristalsis and secretions in the digestive tract. This shift occurs because the body prioritizes immediate survival needs over digestion, redirecting blood flow away from the gastrointestinal organs towards muscles and vital systems. As a result, while in a 'fight or flight' state, digestion is slowed down or temporarily halted to allocate energy where it's most needed.
• Discuss the role of neurotransmitters in the functioning of the sympathetic division and their impact on digestion.
  • Neurotransmitters like norepinephrine are crucial for activating the sympathetic division's responses throughout the body. When faced with a stressful situation, norepinephrine promotes changes such as increased heart rate and muscle readiness while simultaneously inhibiting digestive functions. This inhibition occurs because neurotransmitters signal digestive organs to reduce activity, emphasizing that energy should be conserved for more critical functions during emergencies.
• Evaluate how the interaction between the sympathetic and parasympathetic divisions contributes to overall homeostasis in relation to digestion.
  • The interaction between the sympathetic and parasympathetic divisions is essential for maintaining homeostasis in the body, particularly concerning digestion. While the sympathetic division prepares the body for immediate action by suppressing digestive functions during stress, the parasympathetic division encourages relaxation and digestion when stressors are absent. This balance allows the body to adapt to changing environments; when calm, digestive processes are optimized for nutrient absorption, but under stress, energy is diverted away from these processes to ensure survival.

Related terms

Parasympathetic Division:

The parasympathetic division is the other branch of the autonomic nervous system that promotes 'rest and digest' activities, helping the body to conserve energy and maintain homeostasis.

Autonomic Nervous System: The autonomic nervous system is a component of the peripheral nervous system that regulates involuntary bodily functions, including heart rate, digestion, and respiratory rate.

Neurotransmitters:

Chemical messengers released by neurons that transmit signals across synapses, playing a crucial role in communication within the nervous system, especially during sympathetic responses.