2.6 Flashcards
What are the main respiratory centers in the brainstem?
The main respiratory centers are:
Medullary Respiratory Centers (Dorsal and Ventral Respiratory Groups)
Pneumotaxic Center
Apneustic Center
What is the function of the Dorsal Respiratory Group (DRG)?
The DRG is primarily responsible for generating the basic rhythm of respiration and controlling inspiration by sending signals to the diaphragm and intercostal muscles.
Where is the Ventral Respiratory Group (VRG) located and what is its function?
The VRG is located in the medulla oblongata, ventral to the DRG. It’s involved in both inspiration and expiration, particularly during active breathing, and can increase the rate and depth of breathing when needed.
What is the role of the Pneumotaxic Center?
The Pneumotaxic Center regulates the duration of inspiration, helps switch off inspiratory signals from the DRG, and promotes shorter, more rapid breaths, thus fine-tuning the rhythm of breathing.
What is the function of the Apneustic Center?
The Apneustic Center stimulates prolonged inhalation by providing a continuous excitatory signal to the DRG, helping to regulate the depth of breathing.
What are the two types of chemoreceptors involved in respiratory control?
The two types are:
Central Chemoreceptors (located in the medulla oblongata)
Peripheral Chemoreceptors (located in carotid and aortic bodies)
How do central chemoreceptors respond to changes in CO₂ levels?
When CO₂ levels rise, it diffuses into the CSF, forming carbonic acid and lowering pH. The central chemoreceptors detect this pH change and stimulate the respiratory centers to increase breathing rate and depth.
What is the Hering-Breuer Reflex?
The Hering-Breuer reflex is a physical reflex that prevents overinflation of the lungs. It is activated by stretch receptors in the walls of large airways and lungs, sending inhibitory signals to terminate inspiration and initiate expiration.
How do irritant receptors in the airways function?
Irritant receptors in the airway epithelium are sensitive to irritants like smoke, dust, or noxious gases. When activated, they can trigger coughing, bronchoconstriction, or increased respiratory rate to expel irritants and protect the airways
How does the cerebral cortex influence breathing?
The cerebral cortex allows for voluntary control over breathing, enabling actions like speaking, singing, or holding one’s breath. It can also influence breathing patterns based on emotional states
What role does the hypothalamus play in respiratory control?
The hypothalamus integrates autonomic responses, influencing breathing in response to emotions and body temperature. It can affect respiratory responses during various physiological states, such as fever.
How do bronchodilators affect respiratory patterns?
Bronchodilators, like albuterol, relax bronchial smooth muscle, widening the airways and improving airflow. They help alleviate symptoms of wheezing and shortness of breath in conditions like asthma and COPD.
What effect do opioids have on respiration?
Opioids can depress the respiratory centers in the brainstem, leading to reduced respiratory rate and depth. While effective for pain management, they can cause respiratory depression, especially in overdose situations.
How do sedatives and anxiolytics impact breathing?
Sedatives and anxiolytics, like benzodiazepines, can depress the central nervous system, leading to decreased respiratory drive. They can increase the risk of respiratory depression, particularly in patients with existing respiratory conditions.
