Week 5 - 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 --Conducting ---Terminal --Respiratory -Alveolar duct -Alveolar sacs -Alveolus
What does the conduction zone contain?
Trachea Lungs -Bronchi -Bronchioles --Conducting ---Terminal
What does the respiratory zone contain?
- -Respiratory
- Alveolar duct
- Alveolar sacs
- Alveolus
What are the two types of alveoli cells?
Type I
Type II
Describe Type I alveoli cells
Form the lining
Primary cite of gas exchange
Describe Type II alveoli 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
Pneumatixic 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 wha?
Diaphragm via C3-C5 root
What does the intercostal nerve signal and via wha?
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?
Centrally and peripherally
What are peripheral chemoreceptors located?
Carotid body
Aortic body
What are the muscles involved in respiration?
Diaphragm
Intercostal muscles
Abdominal muscles (rectus abdominus, transverse abdominus, internal/external obliques)
Accessory muscles- sternocleidomstoid, 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”
What happens to the diaphragm and external intercostal muscles during inhalation?
Diaphragm- Flattens
External intercostal muscles- Up and out (elevation of the ribs)
What happens to the diaphragm and external intercostal muscles during exhalation (rest?
Diaphragm and intercostal muscles return to original length due to alveoli containing elastin fibres (elastic recoil)
What is the formula to calculate airway resistance?
= 8nL/Pie(rcubed)
n=viscosity
What is the formula to calculate airflow?
=(p1-p2)/R
During exercise what muscles are used during exhalation?
Internal intercostals
External obliques
Rectus and transverse abdominus
What is the basic function of the medulla oblongata?
Rhymicity- controls basic rate of breathig
What type of neuron is the DRG mainly composed of?
Where does the DRG send impulses to?
Inspiratory
Diaphragm and external intercostal muscles
Where does the DRG receive signal from?
Vagus nerve (X) Glossopharyngeal nerve (IX) Pneumotaxic area Apneustic area Central chemoreceptors
What type of neurons is the VRG mainly composed of?
Where does the VRG send impulses to?
Both inspiratory and expiratory
Laryngeal, pharyngeal, diaphragm, external intercostal muscles (inspiratory signals)
Abdominal muscles, internal/external intercostals (expiratory signals)
Describe the apneustic area
Within the Pons
Prolonged and slow rate of breathing
Overridden by pneumotaxic area
Describe the pneumotaxic area
Within the Pons
Inhibatory impulses and limits duration (to the inspiratory center in the medulla oblongata
What is the product and catalyst for CO2 and H2O?
Carbonic anhydrase
H2CO3 (can lead to HCO3- and H+)
What are the chemoreceptors most sensitive about?
Levels of acidity ([H+])
Where are stretch receptors found?
Within the lungs- smooth muscles of bronchi, bronchioles and visceral pleura)
What volume do the lungs reach when a signal is set and via what nerve is the signal sent?
Roughly 800mL
via vagus nerve- interacts with pneumotaxic area, apneustic area and DRG –> inhibits VRG
Where are irratant receptors found and what nerve is used and what is the outcome?
Nose and bronchioles
Vagus nerve
Sneeze or cough
What disease can the flow volume loop be used to assess?
Obstructive diseases (COPD and asthma) Restrictive diseases
Describe the flow volume loop of someone with an obstructive disease
Same peak, lowers faster (same RV)
Same inhalation
Describe the flow volume loop of someone with an restrictive disease
TLV goes down
Same shape as healthy but all smaller
What does minute ventilation =?
Breathing rate x tidal volume
How does an increase in VE affect pulmonary volumes?
Decrease in IRV
Decreases in ERV
No change in RV
Increase in Vt
What is ventilatory threshold?
“The point at which pulmonary ventilation increases disproportionately with oxygen consumption during graded exercise”
How is ventilatory threshold found?
By plotting:
Ve
VO2
VCO2
What is the respiratory compensation point?
Further increase in Ve to counter change in pH
What is ventilatory equivalents
Amount of air ventilated to obtain 1L of O2 or expire 1L of CO2
