Respiratory Physiology Flashcards
What does the upper respiratory tract contain?
Nose Nasal cavity Mouth Pharynx Larynx
What does the lower respiratory tract contain?
Trachea Lungs -Bronchi -Bronchioles -Alveolar duct -Alveolar sacs -Alveolus
What does the conduction zone contain?
Trachea
Lungs
-Bronchi
-Bronchioles
What does the respiratory zone contain?
- Alveolar duct
- Alveolar sacs
- Alveolus
What are the two types of alveoli cells?
Type I
Type II
Describe Type I alveolar cells
Form the lining
Primary site of gas exchange
Describe Type II alveolar cells
Tiny microvilli
Collecting debris
Pulmonary secretions (reduce alveolar surface tension)
What are the respiratory control centres?
Groups of neurons that control how we breath (depth and frequency)
What are the areas of the pons?
Apneustic area
Pneumotaxic area
What is within the medulla oblongata?
Rhymiticity area
-Ventral and dorsal respiratory group (VRG and DRG)
What does the phrenic nerve signal and via which root
Diaphragm via C3-C5
What does the intercostal nerve signal and via which root
Intercostal muscles via T1-T11 root
What are the types of receptors?
Chemoreceptors
Mechanoreceptors
-Stretch receptors (pressure and distortion)
Irritant receptors
Peripheral Proprioceptors (within muscles and joints)
Where are chemoreceptors?
Carotid body
Aortic body
What are the main muscles involved in respiration?
Diaphragm
Intercostal muscles
What are the accessory muscles involved in respiration?
Abdominal muscles (rectus abdominus, transverse abdominus, internal/external obliques) Sternocleidomastoid, scalenes, pectoralis minor, serratus anterior
What is Boyle’s Law?
“Pressure of a gas in a closed container is inversely proportional to volume of container at a constant temperature”
Describe inhalation (rest)
Diaphragm contracts to become flatter and pushes organs down
External intercostal muscles contract to push ribs up and out
Volume in the chest cavity increases
Pressure drops lower that atmospheric pressure
Air is drawn into the lungs
Describe expiration (rest)
Diaphragm relaxes and is pushed up by organs underneath
External intercostal muscles relax and ribs fall
Volume in the chest cavity decreases
Pressure in the lungs increases above atmospheric pressure
Air is moved out of the lungs
Describe inspiration (exercise)
Diaphragm contracts with more force
External intercostal muscles contract to push ribs up and out with more force
Additional muscles are used:
• Scalenes
• Pectoralis Major
• Sternocleidomastoid
Volume in the chest cavity increases further
Pressure drops lower that atmospheric pressure
More air is drawn into the lungs